A085643 Refines sequence A078812 using permutations and products of exponents on least prime signatures.
1, 2, 1, 3, 4, 1, 4, 6, 4, 6, 1, 5, 8, 12, 9, 12, 8, 1, 6, 10, 16, 9, 12, 36, 8, 12, 24, 10, 1, 7, 12, 20, 24, 15, 48, 36, 27, 16, 72, 32, 15, 40, 12, 1, 8, 14, 24, 30, 16, 18, 60, 48, 72, 54, 20, 96, 144, 54, 16, 20, 120, 80, 18, 60, 14, 1
Offset: 1
Examples
When the signatures (A025487) are listed in A036035 order the number of permutations of the exponents begin 1, 1 1, 1 2 1, 1 2 1 3 1, 1 2 2 3 3 4 1, ... b(n) and the products begin 1, 2 1, 3 2 1, 4 3 4 2 1, 5 4 6 3 4 2 1, ... c(n) thus we can write 1, 2 1, 3 4 1, 4 6 4 6 1, 5 8 12 9 12 8 1, ... a(n) = b(n)*c(n)
Crossrefs
Cf. A078812.
Comments