A086090 a(n) = 2^n + n*3^n.

1, 5, 22, 89, 340, 1247, 4438, 15437, 52744, 177659, 591514, 1950665, 6381388, 20734391, 66977950, 215266373, 688813072, 2195513843, 6973830946, 22083492161, 69736736596, 219669514415, 690387505702, 2165301501629, 6778325652760, 21182248790507, 66088578645418

Offset

0,2

Comments

Binomial transform of A048474

Links

Table of n, a(n) for n=0..26.

Index entries for linear recurrences with constant coefficients, signature (8,-21,18).

Formula

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

E.g.f.: exp(2*x) + 3*x*exp(3*x). - Amiram Eldar, Jan 25 2026

Mathematica

Table[2^n+n*3^n, {n, 0, 30}] (* or *) LinearRecurrence[{8, -21, 18}, {1, 5, 22}, 30] (* Harvey P. Dale, Jun 06 2017 *)

Crossrefs

Cf. A048474, A086091.

Sequence in context: A191008 A006148 A262293 * A037529 A108072 A081892

Adjacent sequences: A086087 A086088 A086089 * A086091 A086092 A086093

Keyword

easy,nonn

Author

Paul Barry, Jul 09 2003

Extensions

More terms from Amiram Eldar, Jan 25 2026

Status

approved