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A151788 Partial sums of A151787. 5
1, 4, 7, 13, 16, 22, 28, 40, 43, 49, 55, 67, 73, 85, 97, 121, 124, 130, 136, 148, 154, 166, 178, 202, 208, 220, 232, 256, 268, 292, 316, 364, 367, 373, 379, 391, 397, 409, 421, 445, 451, 463, 475, 499, 511, 535, 559, 607, 613, 625, 637, 661, 673, 697, 721, 769, 781, 805 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

FORMULA

G.f. g(x) satisfies g(x) = (2+1/x)*(1+x)*g(x^2) + x^2/(1-x). - Robert Israel, Feb 27 2018

MAPLE

wt:= n -> convert(convert(n, base, 2), `+`):

ListTools:-PartialSums([1, seq(3*2^(wt(n-1)-1), n=2..100)]); # Robert Israel, Feb 27 2018

MATHEMATICA

b[n_] := If[n == 1, 1, 3*2^(Total[IntegerDigits[n-1, 2]]-1)];

Array[b, 100] // Accumulate (* Jean-Fran├žois Alcover, Mar 27 2019 *)

PROG

(PARI) b(n) = if (n==1, 1, 3*2^(hammingweight(n-1)-1));

a(n) = sum(k=1, n, b(k)); \\ Michel Marcus, Feb 27 2018

CROSSREFS

Cf. A151787.

Sequence in context: A310806 A125758 A259566 * A310807 A310808 A310809

Adjacent sequences:  A151785 A151786 A151787 * A151789 A151790 A151791

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jun 25 2009

STATUS

approved

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Last modified February 27 15:59 EST 2020. Contains 332307 sequences. (Running on oeis4.)