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Palindromic numbers in bases 2 and 8 written in base 10.
+10
17
0, 1, 3, 5, 7, 9, 27, 45, 63, 65, 73, 195, 219, 325, 341, 365, 381, 455, 471, 495, 511, 513, 585, 1539, 1755, 2565, 2709, 2925, 3069, 3591, 3735, 3951, 4095, 4097, 4161, 4617, 4681, 12291, 12483, 13851, 14043, 20485, 20613, 20805, 20933, 21525, 21653, 21845, 21973, 23085, 23213, 23405, 23533, 24125, 24253, 24445, 24573, 28679, 28807, 28999, 29127, 29719, 29847
OFFSET
1,3
FORMULA
Intersection of A006995 and A029803.
EXAMPLE
2709 is in the sequence because 2709_10 = 5225_8 = 101010010101_2.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 8]; If[palQ[pp, 2], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=2; b2=8; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 30000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
base,nonn
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 3 and 6 written in base 10.
+10
16
0, 1, 2, 4, 28, 80, 160, 203, 560, 644, 910, 34216, 34972, 74647, 87763, 122420, 221068, 225064, 6731644, 6877120, 6927700, 7723642, 8128762, 8271430, 77894071, 78526951, 539212009, 28476193256, 200267707484, 200316968444, 201509576804, 201669082004, 231852949304, 232018753064, 232039258376, 333349186006, 2947903946317, 5816975658914, 5817003372578, 11610051837124, 27950430282103, 81041908142188
OFFSET
1,3
COMMENTS
Agrees with the number of minimal dominating sets of the halved cube graph Q_n/2 for at least n=1 to 5. - Eric W. Weisstein, Sep 06 2021
LINKS
FORMULA
Intersection of A014190 and A029953.
EXAMPLE
28 is in the sequence because 28_10 = 44_6 = 1001_3.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 6]; If[palQ[pp, 3], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=3; b2=6; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* Vincenzo Librandi, Jul 15 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 14 2015
STATUS
approved
Palindromic numbers in bases 4 and 6 written in base 10.
+10
16
0, 1, 2, 3, 5, 21, 55, 215, 819, 1885, 7373, 7517, 12691, 14539, 69313, 196606, 1856845, 3314083, 5494725, 33348861, 223892055, 231755895, 322509617, 3614009815, 4036503055, 4165108015, 9233901154, 9330794722, 12982275395, 107074105033, 186398221946, 270747359295, 401478741365, 1809863435625, 2281658774290, 11931403417210, 12761538567790, 12887266632430, 15822654274715, 30255762326713, 46164680151002, 323292550693473, 329536806222753
OFFSET
1,3
LINKS
FORMULA
Intersection of A014190 and A029953.
EXAMPLE
55 is in the sequence because 55_10 = 131_6 = 313_4.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 6]; If[palQ[pp, 4], AppendTo[lst, pp]; Print[pp]]; k++]; lst
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 15 2015
STATUS
approved
Palindromic numbers in bases 3 and 7 written in base 10.
+10
16
0, 1, 2, 4, 8, 16, 40, 100, 121, 142, 164, 242, 328, 400, 1312, 8200, 9103, 14762, 54008, 76024, 108016, 112048, 233920, 532900, 639721, 741586, 2585488, 3316520, 11502842, 24919360, 35664908, 87001616, 184827640, 4346524576, 5642510512, 11641189600, 65304259157, 68095147754, 469837033600, 830172165614, 17136683996456, 21772277941544, 22666883572232, 45221839119556
OFFSET
1,3
FORMULA
Intersection of A014190 and A029954.
EXAMPLE
142 is in the sequence because 142_10 = 262_7 = 12021_3.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 7]; If[palQ[pp, 3], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=3; b2=7; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1] && d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 4 and 7 written in base 10.
+10
16
0, 1, 2, 3, 5, 85, 150, 235, 257, 8802, 9958, 13655, 14811, 189806, 428585, 786435, 9262450, 31946605, 34179458, 387973685, 424623193, 430421657, 640680742, 742494286, 1692399385, 22182595205, 30592589645, 1103782149121, 1134972961921, 1871644872505, 2047644601565, 3205015384750, 3304611554563, 3628335729863, 4467627704385
OFFSET
1,3
FORMULA
Intersection of A014192 and A029954.
EXAMPLE
85 is in the sequence because 85_10 = 151_7 = 1111_4.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 7]; If[palQ[pp, 4], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=4; b2=7; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 6 and 8 written in base 10.
+10
16
0, 1, 2, 3, 4, 5, 7, 154, 178, 203, 5001, 7409, 315721, 567434, 1032507, 46823602, 56939099, 84572293, 119204743, 1420737297, 1830945641, 2115191225, 3286138051, 3292861699, 4061216947, 8094406311, 43253138565, 80375377033, 88574916241, 108218625313, 116606986537, 116755331881, 166787896538, 186431605610, 318743407660, 396619220597, 1756866976011, 4920262093249, 11760498311914, 15804478291811, 15813860880803, 24722285628901, 33004205249575, 55584258482529, 371039856325905, 401205063672537, 516268720555889
OFFSET
1,3
FORMULA
Intersection of A029953 and A029803.
EXAMPLE
178 is in the sequence because 178_10 = 262_8 = 454_6.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 8]; If[palQ[pp, 6], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=6; b2=8; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 2 and 9 written in base 10.
+10
16
0, 1, 3, 5, 7, 127, 255, 273, 455, 6643, 17057, 19433, 19929, 42405, 1245161, 1405397, 1786971, 2122113, 3519339, 4210945, 67472641, 90352181, 133638015, 134978817, 271114881, 6080408749, 11022828069, 24523959661, 25636651261, 25726334461, 28829406059, 1030890430479, 1032991588623, 1085079274815, 1616662113341
OFFSET
1,3
FORMULA
Intersection of A006995 and A029955.
EXAMPLE
273 is in the sequence because 273_10 = 333_9 = 100010001_2.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 9]; If[palQ[pp, 2], AppendTo[lst, pp]; Print[pp]]; k++]; lst
PROG
(Python)
def nextpal(n, base): # m is the first palindrome successor of n in base base
m, pl = n+1, 0
while m > 0:
m, pl = m//base, pl+1
if n+1 == base**pl:
pl = pl+1
n = n//(base**(pl//2))+1
m, n = n, n//(base**(pl%2))
while n > 0:
m, n = m*base+n%base, n//base
return m
n, a2, a9 = 0, 0, 0
while n <= 30:
if a2 < a9:
a2 = nextpal(a2, 2)
elif a9 < a2:
a9 = nextpal(a9, 9)
else: # a2 == a9
print(a2, end=", ")
a2, a9, n = nextpal(a2, 2), nextpal(a9, 9), n+1 # A.H.M. Smeets, Jun 03 2019
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 3 and 9 written in base 10.
+10
16
0, 1, 2, 4, 8, 10, 20, 40, 80, 82, 91, 100, 164, 173, 182, 328, 364, 400, 656, 692, 728, 730, 820, 910, 1460, 1550, 1640, 2920, 3280, 3640, 5840, 6200, 6560, 6562, 6643, 6724, 7300, 7381, 7462, 8038, 8119, 8200, 13124, 13205, 13286, 13862, 13943, 14024, 14600, 14681, 14762, 26248, 26572, 26896, 29200, 29524, 29848, 32152, 32476, 32800, 52496, 52820, 53144, 55448, 55772, 56096, 58400, 58724, 59048, 59050, 59860, 60670, 65620, 66430, 67240, 72190, 73000, 73810
OFFSET
1,3
FORMULA
Intersection of A014190 and A029955.
EXAMPLE
40 is in the sequence because 40_10 = 44_9 = 1111_3.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 9]; If[palQ[pp, 3], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=3; b2=9; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 80000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved
Palindromic numbers in bases 7 and 9 written in base 10.
+10
16
0, 1, 2, 3, 4, 5, 6, 8, 40, 50, 100, 164, 200, 264, 300, 328, 400, 2000, 3550, 8200, 10252, 14510, 14762, 22800, 45600, 164900, 201720, 400200, 532900, 555013, 738100, 2756120, 2913368, 3344352, 3501600, 4084000, 12990350, 22674550, 194062432, 1684866370, 2225211080, 13575144288, 15127811455, 20404027400, 20537111057, 22668403353, 30862471355, 83714515310, 84668107250, 796259955485, 1202029647736, 2088800185930, 20268849562000
OFFSET
1,3
FORMULA
Intersection of A029954 and A029955.
EXAMPLE
264 is in the sequence because 264_10 = 323_9 = 525_7.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 9]; If[palQ[pp, 7], AppendTo[lst, pp]; Print[pp]]; k++]; lst
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 17 2015
STATUS
approved
Palindromic numbers in bases 3 and 8 written in base 10.
+10
15
0, 1, 2, 4, 121, 130, 203, 316, 8578, 9490, 17492, 944035, 1141652, 1276916, 1554173, 58961443, 67470916, 4099065139, 5691134677, 81452592329, 81473867465, 419572845958, 21056462595764, 363376288168081
OFFSET
1,3
FORMULA
Intersection of A014190 and A029803.
EXAMPLE
121 is in the sequence because 121_10 = 171_8 = 11111_3.
MATHEMATICA
(* first load nthPalindromeBase from A002113 *) palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; k = 0; lst = {}; While[k < 21000000, pp = nthPalindromeBase[k, 8]; If[palQ[pp, 3], AppendTo[lst, pp]; Print[pp]]; k++]; lst
b1=3; b2=8; lst={}; Do[d1=IntegerDigits[n, b1]; d2=IntegerDigits[n, b2]; If[d1==Reverse[d1]&&d2==Reverse[d2], AppendTo[lst, n]], {n, 0, 10000000}]; lst (* Vincenzo Librandi, Jul 17 2015 *)
KEYWORD
nonn,base
AUTHOR
Eric A. Schmidt and Robert G. Wilson v, Jul 16 2015
STATUS
approved

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