1,2

a(n) is the index k such that A093903(k) = n.

5 and 7 do not appear up to position 100000, 6 appears at position 3, and 8 to 21 appear resp. at 673, 10, 25493, 4, 21, 50, 121, 6, 19, 48, 17, 8, 119, 10132.

A093903(7) = 2, so a(2) = 7.

Cf. A093903.

Sequence in context: A126561 A144875 A049477 this_sequence A117237 A011477 A093072

Adjacent sequences: A113956 A113957 A113958 this_sequence A113960 A113961 A113962

nonn,bref,more

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Nov 10 2005