A323825 Number of ways of having a total of n coins in your two pockets (each of them either a penny, a nickel, a dime, or a quarter), so that the amounts in the pockets are identical.

1, 0, 4, 2, 12, 12, 34, 40, 85, 108, 190, 250, 394, 516, 762, 984, 1385, 1764, 2396, 2998, 3966, 4886, 6316, 7684, 9739, 11706, 14594, 17358, 21320, 25134, 30470, 35618, 42697, 49532, 58770, 67724, 79622, 91172, 106326, 121048, 140117, 158692, 182452, 205624

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..10000

Shalosh B. Ekhad and Doron Zeilberger, In How many ways can I carry a total of n coins in my two pockets, and have the same amount in both pockets?, arXiv:1901.08172 [math.CO], 2019.

Formula

Ekhad-Zeilberger (2019) gives a g.f.

Crossrefs

Sequence in context: A227043 A143376 A111667 * A019239 A143944 A154345

Adjacent sequences: A323822 A323823 A323824 * A323826 A323827 A323828

Keyword

nonn,easy

Author

N. J. A. Sloane, Feb 01 2019

Status

approved