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A155590 7^n+2^n-1^n. 21
1, 8, 52, 350, 2416, 16838, 117712, 823670, 5765056, 40354118, 282476272, 1977328790, 13841291296, 96889018598, 678223089232, 4747561542710, 33232930635136, 232630514118278, 1628413598172592, 11398895185897430 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..19.

Index entries for linear recurrences with constant coefficients, signature (10,-23,14).

FORMULA

G.f.: 1/(1-7*x)+1/(1-2*x)-1/(1-x). E.g.f.: e^(7*x)+e^(2*x)-e^x.

a(n)=9*a(n-1)-14*a(n-2)-6 with a(0)=1, a(1)=8 - Vincenzo Librandi, Jul 21 2010

PROG

(PARI) a(n)=7^n+2^n-1 \\ Charles R Greathouse IV, Sep 24 2015

CROSSREFS

Cf. A074501, A074600, A005057, A005056, A099393, A155588, A155590.

Sequence in context: A205218 A287813 A126503 * A130153 A199700 A302865

Adjacent sequences:  A155587 A155588 A155589 * A155591 A155592 A155593

KEYWORD

nonn,easy

AUTHOR

Mohammad K. Azarian, Jan 24 2009

STATUS

approved

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Last modified April 13 09:12 EDT 2021. Contains 342935 sequences. (Running on oeis4.)