A119849 Nonzero values of A119842, in order of appearance.

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 6, 1, 2, 1, 1, 1, 14, 1, 1, 1, 1, 1, 1, 1, 1, 22, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 14, 1, 1, 1, 1, 1, 2, 1, 252, 1, 1, 1, 5, 1, 2

Offset: 1

Author

Antti Karttunen, Jun 04 2006

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..3323

Crossrefs

a(n) = A119842(A119848(n)).

Programs

Mathematica

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[ k = 1, k < 200, k++, If[a[k] > 0, Print[k, " ", a[k]]; Sow[a[k]]]]][[2, 1]] (* Jean-François Alcover, Mar 03 2016, after Alois P. Heinz *)