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A127804 a(2n)=4^n, a(4*n+3)-(2^(4*n+3)+2^(2*n+1))=a(n). 4
1, 3, 4, 11, 16, 36, 64, 139, 256, 528, 1024, 2084, 4096, 8256, 16384, 32907, 65536, 131328, 262144, 524816, 1048576, 2098176, 4194304, 8390692, 16777216, 33558528, 67108864, 134225984, 268435456 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Row sums of number triangle A127803.

LINKS

Table of n, a(n) for n=0..28.

FORMULA

Conjecture: a(n) = 1 + A187767(n+1). - Andrew Howroyd, Jun 02 2017

MATHEMATICA

rows = 30;

A[n_, k_] := If[k <= n, If[n <= 2 k, 1/(2*2^n - 1), 0], 0];

T = Table[A[n, k], {n, 0, rows-1}, {k, 0, rows-1}] // Inverse;

a[n_] := T[[n+1]] // Total;

Table[a[n], {n, 0, rows-1}] (* Jean-Fran├žois Alcover, Jul 03 2018 *)

CROSSREFS

Cf. A127803, A187767.

Sequence in context: A248825 A001641 A007382 * A027306 A239024 A026676

Adjacent sequences:  A127801 A127802 A127803 * A127805 A127806 A127807

KEYWORD

nonn

AUTHOR

Paul Barry, Jan 29 2007

STATUS

approved

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Last modified August 24 22:41 EDT 2019. Contains 326314 sequences. (Running on oeis4.)