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A130586 Row sums of triangle A130585. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 21 20:44 EDT 2019. Contains 328315 sequences. (Running on oeis4.)