A295904 Number of (not necessarily maximal) cliques in the n-sun graph.

6, 12, 20, 32, 52, 88, 156, 288, 548, 1064, 2092, 4144, 8244, 16440, 32828, 65600, 131140, 262216, 524364, 1048656, 2097236, 4194392, 8388700, 16777312, 33554532, 67108968, 134217836, 268435568, 536871028, 1073741944, 2147483772, 4294967424, 8589934724

Offset

1,1

Comments

Extended to a(1)-a(2) using the formula.

Links

Table of n, a(n) for n=1..33.

Eric Weisstein's World of Mathematics, Clique

Eric Weisstein's World of Mathematics, Sun Graph

Index entries for linear recurrences with constant coefficients, signature (4, -5, 2).

Formula

a(n) = 2^n + 4*n.

a(n) = 4*a(n-1) - 5*a(n-2) + 2*a(n-3).

G.f.: -2*x*(3 - 6*x + x^2)/((-1 + x)^2*(-1 + 2*x)).

Mathematica

Table[2^n + 4 n, {n, 20}]
LinearRecurrence[{4, -5, 2}, {6, 12, 20}, 20]
CoefficientList[Series[-2 (3 - 6 x + x^2)/((-1 + x)^2 (-1 + 2 x)), {x, 0, 20}], x]

Crossrefs

Sequence in context: A326378 A064971 A130199 * A309836 A117343 A286290

Adjacent sequences: A295901 A295902 A295903 * A295905 A295906 A295907

Keyword

nonn,easy

Author

Eric W. Weisstein, Nov 29 2017

Status

approved