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%I #8 Feb 08 2017 19:04:15
%S 17,23,47,57,93,107,155,173,233,255,327,353,437,467,563,597,677,705,
%T 743,863,905,1037,1083,1187,1227,1277,1433,1487,1607,1655,1713,1893,
%U 1955,2027,2095,2147,2213,2293,2357,2417,2467,2487,2503,2703,2719,2777,2861,2993,3005,3083,3251
%N Numbers such that A279967(n) = 0.
%C This sequence is neither a subset nor a superset of sequence A278436 since 155 and 817 are in one, but not the other, respectively.
%e Number 155 = 5*31, equivalent to array position (17, 2), is in the sequence since all prior numbers in column 1 are even as are those in column 2, except 9 which is not a factor of 155.
%t (* support functions are in A279967*)
%t a281533[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=Apply[Plus, Select[Map[ms[[Apply[Sequence, #]]]&, priorPos[pos]], #!=0 && Mod[seqPos[pos], #]==0&]]; If[val==0,AppendTo[seqL, val]]; ms[[Apply[Sequence, pos]]]=val]; seqL]
%t a281533[81] (* data *)
%Y Cf. A278436, A279966, A279967.
%K nonn
%O 1,1
%A _Hartmut F. W. Hoft_, Jan 23 2017
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