A034872 Central column of Losanitsch's triangle A034851.

1, 1, 1, 2, 4, 6, 10, 19, 38, 66, 126, 236, 472, 868, 1716, 3235, 6470, 12190, 24310, 46252, 92504, 176484, 352716, 676270, 1352540, 2600612, 5200300, 10030008, 20060016, 38781096, 77558760, 150273315, 300546630, 583407990, 1166803110, 2268795980, 4537591960, 8836340260, 17672631900

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

N. J. A. Sloane, Classic Sequences

Mathematica

Table[(1/2)*(Binomial[n, Floor[n/2]] + Binomial[Mod[n, 2], Mod[Floor[n/2], 2]]*Binomial[Floor[n/2], Floor[Floor[n/2]/2]]), {n, 0, 50}] (* G. C. Greubel, Feb 23 2018 *)

Prog

(PARI) for(n=0, 50, print1((1/2)*(binomial(n, n\2) + binomial(n%2, (n\2)%2)* binomial(n\2, (n\2)\2)), ", ")) \\ G. C. Greubel, Feb 23 2018
(Magma) [(1/2)*(Binomial(n, Floor(n/2)) + Binomial(n mod 2, Floor(n/2) mod 2)*Binomial(Floor(n/2), Floor(Floor(n/2)/2))): n in [0..50]]; // G. C. Greubel, Feb 23 2018

Crossrefs

Sequence in context: A026680 A317639 A164141 * A032362 A282251 A176716

Adjacent sequences: A034869 A034870 A034871 * A034873 A034874 A034875

Keyword

nonn

Author

N. J. A. Sloane

Extensions

Terms a(32) onward added by G. C. Greubel, Feb 23 2018

Status

approved