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 A278436 Numbers such that A279966(n) = 0. 3

%I

%S 17,23,47,57,93,107,173,233,353,437,467,563,677,743,817,829,851,863,

%T 955,1037,1187,1213,1277,1387,1433,1487,1549,2089,2147,2213,2287,2293,

%U 2417,2473,2689,2777,2911,3083,3323,3391,6691,9337,22969,38557,47347,75391,104999,130927,146719

%N Numbers such that A279966(n) = 0.

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

%C 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

%e 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

%t (* support functions are in A279967*)

%t 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]

%t a278436[500] (* data through 104999. - _Hartmut F. W. Hoft_, Jan 23 2017 *)

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

%K nonn

%O 1,1

%A _Alec Jones_, Dec 24 2016

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Last modified April 6 18:34 EDT 2020. Contains 333286 sequences. (Running on oeis4.)