A130586 Row sums of triangle A130585.

1, 3, 9, 19, 65, 75, 385, 531, 1545, 2115, 10241, 8283, 49153, 49539, 131145, 262675, 1048577, 788043, 4718593, 4196435, 12583305, 20981763, 92274689, 67117659, 335544385, 402702339, 1207961097, 1610662291, 7516192769, 4295100555

Offset

0,2

Comments

A130584 row sums = A001792, the binomial transform of [1,2,3,...]: (1, 3, 8, 20, 48, 112, ...).

Links

Table of n, a(n) for n=0..29.

Formula

Row sums of A130585.

a(n-1) = Sum_{d|n} phi(n/d)*2^(n/d - 1). [Olivier Gérard, Jan 01 2012]

Example

a(3) = 19 = sum of row 3 terms of A130585: (4 + 7 + 6 + 2).

Mathematica

Table[Plus@@Map[Function[d, EulerPhi[(n+1)/d] 2^((n+1)/d-1)], Divisors[n+1]], {n, 0, 30}] (* Olivier Gérard, Jan 01 2012 *)

Crossrefs

Cf. A130585, A001792, A130584.

Sequence in context: A018316 A146605 A147070 * A147146 A146066 A164283

Adjacent sequences: A130583 A130584 A130585 * A130587 A130588 A130589

Keyword

nonn

Author

Gary W. Adamson, Jun 06 2007

Extensions

More terms from Olivier Gérard, Jan 01 2012

Status

approved