A028321 Even elements to the right of the central elements of the 5-Pascal triangle A028313.

6, 8, 36, 10, 46, 12, 378, 204, 840, 582, 82, 14, 1422, 96, 3102, 1210, 16, 562, 8866, 5148, 144, 18, 14014, 2912, 162, 20, 78078, 55848, 31668, 14028, 4740, 1176, 165308, 133926, 87516, 45696, 18768, 5916, 222, 22, 299234, 221442, 133212

Offset: 0

Author

Mohammad K. Azarian

Keywords

• nonn
• tabf

Links

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

Crossrefs

Cf. A028313, A028314, A028315, A028316, A028317, A028318, A028319.

Cf. A028320, A028322, A028323, A028324, A028325, A051472.

Programs

Magma

T:= func< n, k | n le 1 select 1 else Binomial(n, k) + 3*Binomial(n-2, k-1) >; // T = A028323
b:=[T(n, k): k in [1+Floor(n/2)..n], n in [0..100]];
[b[n]: n in [1..150] | (b[n] mod 2) eq 0]; // G. C. Greubel, Jul 02 2024

Mathematica

b:= Table[If[n<2, 1, Binomial[n,k] +3*Binomial[n-2,k-1]], {n,0,30}, {k, Floor[n/2]+1, n}]//Flatten;
Select[b, EvenQ] (* G. C. Greubel, Jul 02 2024 *)

SageMath

def A028323(n, k): return binomial(n, k) + 3*binomial(n-2, k-1) - 3*int(n==0)
b=flatten([[A028323(n, k) for k in range(1+(n//2),n+1)] for n in range(101)])
[b[n] for n in (1..150) if b[n]%2==0] # G. C. Greubel, Jul 02 2024

Extensions

More terms from James Sellers