A308600 Number of (not necessarily maximal) cliques in the n X n antelope graph.

2, 5, 10, 17, 34, 61, 98, 145, 202, 269, 346, 433, 530, 637, 754, 881, 1018, 1165, 1322, 1489, 1666, 1853, 2050, 2257, 2474, 2701, 2938, 3185, 3442, 3709, 3986, 4273, 4570, 4877, 5194, 5521, 5858, 6205, 6562, 6929, 7306, 7693, 8090, 8497, 8914, 9341, 9778, 10225, 10682, 11149

Offset

1,1

Links

Colin Barker, Table of n, a(n) for n = 1..1000

Eric Weisstein's World of Mathematics, Antelope Graph

Eric Weisstein's World of Mathematics, Clique

Index entries for linear recurrences with constant coefficients, signature (3,-3,1).

Formula

a(n) = 5*n^2-28*n+49 for n >= 3.

From Colin Barker, Jun 10 2019: (Start)

G.f.: x*(2 - x + x^2 + 8*x^4) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>5.

(End)

Mathematica

Table[Piecewise[{{2, n == 1}, {5, n == 2}}, 49 - 28 n + 5 n^2], {n, 20}]

Prog

(PARI) Vec(x*(2 - x + x^2 + 8*x^4) / (1 - x)^3 + O(x^50)) \\ Colin Barker, Jun 10 2019

Crossrefs

Sequence in context: A227363 A342172 A262406 * A308604 A018315 A146220

Adjacent sequences: A308597 A308598 A308599 * A308601 A308602 A308603

Keyword

nonn,easy

Author

Eric W. Weisstein, Jun 09 2019

Status

approved