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A180125 Self-convolution of period-doubling sequence A035263 0
0, 1, 0, 2, 2, 3, 2, 5, 2, 5, 2, 6, 4, 7, 4, 10, 6, 9, 6, 12, 8, 11, 8, 15, 8, 13, 8, 16, 10, 15, 10, 21, 10, 17, 10, 20, 12, 19, 12, 25, 12, 21, 12, 24, 14, 23, 14, 30, 16, 25, 16, 30, 18, 27, 18, 35, 18, 29, 18, 34, 20, 31, 20, 42, 22, 33, 22, 40, 24, 35, 24, 45, 24, 37 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Reducing a(n) mod 2 gives 1-A035263(n), which is also A096268(n+1).

LINKS

Table of n, a(n) for n=1..74.

FORMULA

a(n) = sum(b(i)b(n-i), i=1..(n-1)), where b(i)=A035263(i).

MATHEMATICA

b[i_] := b[i] = If[OddQ[i], 1, 1 - b[i/2]]; a[n_] := Sum[b[i] b[n - i], {i, 1, n - 1}]

CROSSREFS

Cf. A035263, A096268

Sequence in context: A010846 A073023 A173754 * A272209 A326842 A326843

Adjacent sequences:  A180122 A180123 A180124 * A180126 A180127 A180128

KEYWORD

nonn

AUTHOR

Jacob A. Siehler, Aug 11 2010

STATUS

approved

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Last modified January 17 17:03 EST 2021. Contains 340247 sequences. (Running on oeis4.)