A081627 2*7^n-5^n.

1, 9, 73, 561, 4177, 30489, 219673, 1568961, 11138977, 78754089, 555184873, 3905825361, 27438433777, 192557317689, 1350342630073, 9464605441761, 66313273248577, 464498088521289, 3253012498555273, 22778716884418161

Offset

0,2

Comments

Binomial transform of A081626.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (12,-35).

Formula

G.f.: (1-3*x)/((1-5*x)*(1-7*x)).

E.g.f. 2*exp(7*x)-exp(5*x).

Mathematica

CoefficientList[Series[(1 - 3 x) / ((1 - 5 x) (1 - 7 x)), {x, 0, 40}], x] (* Vincenzo Librandi, Aug 09 2013 *)

Prog

(Magma) [2*7^n-5^n: n in [0..25]]; // Vincenzo Librandi, Aug 09 2013

Crossrefs

Sequence in context: A079927 A126641 A346229 * A164588 A023001 A277672

Adjacent sequences: A081624 A081625 A081626 * A081628 A081629 A081630

Keyword

easy,nonn

Author

Paul Barry, Mar 25 2003

Status

approved