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A278436 Numbers such that A279966(n) = 0. 3
17, 23, 47, 57, 93, 107, 173, 233, 353, 437, 467, 563, 677, 743, 817, 829, 851, 863, 955, 1037, 1187, 1213, 1277, 1387, 1433, 1487, 1549, 2089, 2147, 2213, 2287, 2293, 2417, 2473, 2689, 2777, 2911, 3083, 3323, 3391, 6691, 9337, 22969, 38557, 47347, 75391, 104999, 130927, 146719 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Not all numbers in this list are prime; nonprime elements include 57, 93, 437, 817, 851, 955, 1037, 1387, 2147.

This sequence is neither a subset nor a superset of sequence A281533 since 155 and 817 are the first numbers in one, but not the other, respectively. - Hartmut F. W. Hoft, Jan 23 2017

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

Number 817 = 19*43, equivalent to array position (4, 37), is in the sequence since none of the numbers in the prior column, diagonal, row and antidiagonal contain the counts of 1, 19, 43 and 817. - Hartmut F. W. Hoft, Jan 23 2017

MATHEMATICA

(* support functions are in A279967*)

a278436[k_] := Module[{ut=upperTriangle[k], ms=Table[" ", {i, 1, k}, {j, 1, k}], h, pos, val, seqL={}}, ms[[1, 1]]=1; For[h=2, h<=Length[ut], h++, pos=ut[[h]]; val=Length[Select[Map[ms[[Apply[Sequence, #]]]&, priorPos[pos]], #!=0 && Mod[seqPos[pos], #]==0&]]; If[val==0, AppendTo[seqL, h]; ms[[Apply[Sequence, pos]]]=val]; seqL]

a278436[500] (* data through 104999. - Hartmut F. W. Hoft, Jan 23 2017 *)

CROSSREFS

Cf. A279966, A000124, A145018, A152948, A152950, A167499, A279967.

Sequence in context: A159044 A267984 A281533 * A126329 A130098 A046123

Adjacent sequences:  A278433 A278434 A278435 * A278437 A278438 A278439

KEYWORD

nonn

AUTHOR

Alec Jones, Dec 24 2016

STATUS

approved

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Last modified February 25 23:44 EST 2020. Contains 332270 sequences. (Running on oeis4.)