OFFSET
1,3
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..94 (first 82 terms from Chai Wah Wu)
MATHEMATICA
palQ[n_Integer, base_Integer] := Block[{}, Reverse[ idn = IntegerDigits[n, base]] == idn]; genPal[n_] := Block[{id = IntegerDigits@ n, insert = {{}, {0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}, {8}, {9}}}, FromDigits@ Join[id, #, Reverse@ id] & /@ insert]; k = 1; lst = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}; While[k < 1000001, s = Select[ genPal[k], palQ[#, 25] &]; If[s != {}, AppendTo[lst, s]; Print@ s; lst = Sort@ Flatten@ lst]; k++]; lst
PROG
(Magma) [n: n in [0..10000000] | Intseq(n) eq Reverse(Intseq(n))and Intseq(n, 25) eq Reverse(Intseq(n, 25))]; // Vincenzo Librandi, Nov 23 2014
(Python)
from gmpy2 import digits
def palQ(n, b): # check if n is a palindrome in base b
s = digits(n, b)
return s == s[::-1]
def palQgen10(l): # unordered generator of palindromes of length <= 2*l
if l > 0:
yield 0
for x in range(1, 10**l):
s = str(x)
yield int(s+s[-2::-1])
yield int(s+s[::-1])
A250410_list = sorted([n for n in palQgen10(6) if palQ(n, 25)])
# Chai Wah Wu, Nov 25 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, Nov 22 2014
STATUS
approved