1,1

Create a table with tau(2^n-1) as the first row (A046801) and tau(m) as the first column (A000005). The second column is tau(A004760) and so on. Rows 2, 3 and 4 are easily described in terms of row 1. This sequence is row 5.

Table of n, a(n) for n=1..92.

a[ n ] = DivisorSigma [ 0, 4*(2^n -1)+1 ] ]

Sequence in context: A241514 A125913 A122386 * A151565 A060632 A160407

Adjacent sequences: A051461 A051462 A051463 * A051465 A051466 A051467

nonn

Edwin D. Evans, eevans2(AT)pacbell.net

approved