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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
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
Sequence in context: A159044 A267984 A281533 * A126329 A130098 A046123
KEYWORD
nonn
AUTHOR
Alec Jones, Dec 24 2016
STATUS
approved

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Last modified April 25 13:12 EDT 2024. Contains 371969 sequences. (Running on oeis4.)