1,2

Inverse Mobius transform of A001227, the number of odd divisors of n. Row sums of triangle A133699.

a(4) = sum of row 4 terms of triangle A133699: (1 + 1 + 0 + 1) = (1, 1, 0, 1) dot (1, 1, 2, 1), where A001227 = (1, 1, 2, 1, 2, 2, 2, 1, 3,...).

Cf. A133700, A001227.

Sequence in context: A119688 A134187 A078644 this_sequence A087688 A126854 A115206

Adjacent sequences: A133697 A133698 A133699 this_sequence A133701 A133702 A133703

nonn

Gary W. Adamson (qntmpkt(AT)yahoo.com), Sep 21 2007