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Revision History for A349298 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

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Positions k in row n of triangles S(n,k) = T(n,k) = 0, where A054521 = S and A349297 = T, or 0 if there are no such k.
(history; published version)
#10 by N. J. A. Sloane at Thu Dec 09 01:00:49 EST 2021
STATUS

reviewed

approved

#9 by Michel Marcus at Thu Dec 09 00:39:51 EST 2021
STATUS

proposed

reviewed

#8 by Michael De Vlieger at Wed Dec 08 22:29:46 EST 2021
STATUS

editing

proposed

#7 by Michael De Vlieger at Wed Dec 08 22:18:14 EST 2021
MATHEMATICA

With[{s = Merge[Map[#1 -> #2 & @@ # &, Position[ImageData[#], 0.]], Identity]}, Array[If[KeyExistsQ[s, #], Lookup[s, #], {0}] &, ImageDimensions[#][[-1]]] // Flatten] &@ Import["https://oeis.org/A349298/a349298.png"] (* Generate 1024 rows stored in the bitmap image, Michael De Vlieger, Dec 08 2021 *)

#6 by Michael De Vlieger at Wed Dec 08 22:15:32 EST 2021
LINKS

Michael De Vlieger, <a href="/A349298/a349298.png">1024-pixel bitmap</a> plotting (n, T(n,k)) in black, otherwise white including for rows containing 0.

#5 by Michael De Vlieger at Wed Dec 08 22:12:27 EST 2021
LINKS

Michael De Vlieger, <a href="/A349298/b349298.txt">Table of n, a(n) for n = 1..10635</a> (rows 1 <= n <= 600, flattened)

MATHEMATICA

With[{nn = 45}, Table[If[Length[#] == 0, {0}, #] &@ Select[Array[# Boole[Xor[Or[Mod[#, 2] == Mod[n, 2] == 0, Mod[#, 3] == Mod[n, 3] == 0], GCD[n, #] != 1]] &, n], # > 0 &], {n, nn}]] // Flatten (* Michael De Vlieger, Dec 08 2021 *)

STATUS

approved

editing

#4 by Susanna Cuyler at Sun Nov 14 23:52:47 EST 2021
STATUS

proposed

approved

#3 by Michael De Vlieger at Sun Nov 14 22:50:56 EST 2021
STATUS

editing

proposed

#2 by Michael De Vlieger at Sat Nov 13 22:28:40 EST 2021
NAME

allocated for Michael De VliegerPositions k in row n of triangles S(n,k) = T(n,k) = 0, where A054521 = S and A349297 = T, or 0 if there are no such k.

DATA

0, 0, 0, 0, 5, 0, 7, 0, 0, 5, 11, 0, 13, 7, 5, 10, 0, 17, 0, 19, 5, 15, 7, 14, 11, 23, 0, 5, 10, 15, 20, 25, 13, 0, 7, 21, 29, 5, 25, 31, 0, 11, 22, 17, 5, 7, 10, 14, 15, 20, 21, 25, 28, 30, 35, 0, 37, 19, 13, 26, 5, 15, 25, 35, 41, 7, 35, 43, 11, 33, 5, 10, 20, 25, 35, 40

OFFSET

1,5

COMMENTS

Row n is a list of k for which A349297 NOR A054521 is true.

Row p > 3 for p prime has the single term p.

Nonzero terms in this sequence are of the form k*m > 1, where 3-smooth k > 1 in A003586 and 5-rough m > 1 in A007310, with m mod 6 = +/- 1.

EXAMPLE

Table T(n,k) for 1 <= n <= 16, replacing 0 with "." and 1 with "*", showing terms in row n of this sequence. Rows with no terms are replaced by 0:

1: .

2: . *

3: . . *

4: . * . *

5: . . . . 5

6: . * * * . *

7: . . . . . . 7

8: . * . * . * . *

9: . . * . . * . . *

10: . * . * 5 * . * . *

11: . . . . . . . . . . 11

12: . * * * . * . * * * . *

13: . . . . . . . . . . . . 13

14: . * . * . * 7 * . * . * . *

15: . . * . 5 * . . * 10 . * . . *

16: . * . * . * . * . * . * . * . *

---------------------------------------------------

n\k 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Hence, row 5 = {5}, row 7 = {7}, row 11 = {11}, row 13 = {13}, row 14 = {7}, row 15 = {5, 10}, and all other rows 1 <= n <= 16 have no terms, thus are assigned 0 by definition.

CROSSREFS
KEYWORD

allocated

nonn,tabf

AUTHOR

Michael De Vlieger, Nov 13 2021

STATUS

approved

editing

#1 by Michael De Vlieger at Sat Nov 13 15:16:00 EST 2021
NAME

allocated for Michael De Vlieger

KEYWORD

allocated

STATUS

approved