A349975 Expansion of g.f. (x^4*(x^2 + 2*x + 3))/((x - 1)^4*(x + 1)*(x^2 + x + 1)).

0, 0, 0, 0, 3, 8, 17, 31, 51, 77, 112, 155, 208, 272, 348, 436, 539, 656, 789, 939, 1107, 1293, 1500, 1727, 1976, 2248, 2544, 2864, 3211, 3584, 3985, 4415, 4875, 5365, 5888, 6443, 7032, 7656, 8316, 9012, 9747, 10520, 11333, 12187, 13083, 14021, 15004, 16031, 17104

Offset

0,5

Comments

Number of subsets of [n] having a distset (set of distances, see definition in A349976) of cardinality 4.

Links

Table of n, a(n) for n=0..48.

Index entries for linear recurrences with constant coefficients, signature (2,0,-1,-1,0,2,-1).

Crossrefs

Column k=4 of A349976.

Sequence in context: A033816 A011889 A188426 * A105163 A011850 A141422

Adjacent sequences: A349972 A349973 A349974 * A349976 A349977 A349978

Keyword

nonn,easy

Author

Peter Luschny, Dec 10 2021

Status

approved