A026034 a(n) = A026022(n,floor(n/2)).

1, 1, 2, 3, 6, 10, 20, 35, 69, 125, 242, 451, 858, 1638, 3068, 5980, 11050, 21930, 40052, 80750, 145996, 298452, 534888, 1106921, 1968685, 4118725, 7276050, 15371475, 26993490, 57528750, 100490220, 215867880, 375287550, 811985790, 1405622460, 3061229850

Offset

0,3

Links

Table of n, a(n) for n=0..35.

Formula

a(2*n) = A026029(n), a(2*n+1) = A026026(n+2).

a(n) = binomial(n, floor(n/2)) - binomial(n, floor(n/2) - 4). - Christian Krause, May 09 2026

Crossrefs

Cf. A026022, A026026, A026029.

Sequence in context: A180272 A319436 A061551 * A178381 A037031 A336675

Adjacent sequences: A026031 A026032 A026033 * A026035 A026036 A026037

Keyword

nonn,easy

Author

Clark Kimberling

Status

approved