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A048641 Partial sums of A003188 (Gray code). 2
0, 1, 4, 6, 12, 19, 24, 28, 40, 53, 68, 82, 92, 103, 112, 120, 144, 169, 196, 222, 252, 283, 312, 340, 360, 381, 404, 426, 444, 463, 480, 496, 544, 593, 644, 694, 748, 803, 856, 908, 968, 1029, 1092, 1154, 1212, 1271, 1328, 1384, 1424, 1465, 1508, 1550, 1596 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..53.

R. Stephan, Some divide-and-conquer sequences ...

R. Stephan, Table of generating functions

FORMULA

a(2^n-1) = A000217(2^n-1) for all n.

a(n) = sum(XORnos(j, floor(j/2)), j=0..n)

a(n) = b(n-1), with b(2n)=2*(b(n)+b(n-1)+ceil(n/2)), b(2n+1)=4*b(n)+n+1. - Ralf Stephan, Sep 13 2003

MATHEMATICA

Accumulate[Table[BitXor[n, Floor[n/2]], {n, 0, 100}]] (* Vladimir Joseph Stephan Orlovsky, Jul 19 2011 *)

PROG

(PARI) a(n) = sum(k=0, n, bitxor(k, k>>1)); \\ Michel Marcus, Oct 02 2015

CROSSREFS

Cf. A000217, A003188.

Sequence in context: A079865 A059961 A027856 * A023599 A087881 A063607

Adjacent sequences:  A048638 A048639 A048640 * A048642 A048643 A048644

KEYWORD

easy,nonn

AUTHOR

Antti Karttunen, Jul 14 1999

STATUS

approved

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Last modified October 20 06:05 EDT 2018. Contains 316378 sequences. (Running on oeis4.)