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A119843 A119842(n) sets a new record. 2

%I

%S 1,36,72,120,144,180,420,720,1080,1680,2520,6300,9240

%N A119842(n) sets a new record.

%C a(9) is greater than 960.

%t b[s_, t_] := b[s, t] = If[Length[s] < 1, 1, Sum[If[Mod[PrimeOmega[x], 2] == 1 - t && Length[Select[s, Mod[#, x] == 0 &]] == 1, b[s~Complement~{x}, 1 - t], 0], {x, s}]]; a[n_] := a[n] = Module[{l, m}, l = Sort[ FactorInteger[n], #1[[2]] > #2[[2]] &]; m = Product[Prime[i]^l[[i]][[2]], {i, 1, Length[l]}]; b[Divisors[m][[2 ;; -2]], Mod[PrimeOmega[m], 2]]]; Reap[For[record = 0; k = 1, k < 10^4, k++, If[a[k] > record, record = a[k]; Print[k, " ", a[k]]; Sow[k]]]][[2, 1]] (* _Jean-Fran├žois Alcover_, Mar 03 2016, after _Alois P. Heinz_ *)

%Y Subset of A119845. Cf. A119844.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jun 04 2006

%E a(9)-a(13) from _Alois P. Heinz_, Feb 26 2016

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Last modified February 19 22:38 EST 2019. Contains 320328 sequences. (Running on oeis4.)