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A092808 Pair reversal of Jacobsthal numbers. 4
1, 0, 3, 1, 11, 5, 43, 21, 171, 85, 683, 341, 2731, 1365, 10923, 5461, 43691, 21845, 174763, 87381, 699051, 349525, 2796203, 1398101, 11184811, 5592405, 44739243, 22369621, 178956971, 89478485, 715827883, 357913941, 2863311531, 1431655765 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(2n)=A001045(2n+1); a(2n+1)=A001045(2n) a(2n+2)=a(2n)+2*4^n; a(2n+3)=a(2n+1)+4^n.

LINKS

Table of n, a(n) for n=0..33.

Index entries for linear recurrences with constant coefficients, signature (-1,4,4).

FORMULA

G.f.: (1+x-x^2)/((1+x)(1-2x)(1+2x)); E.g.f.: exp(-2x)/4+5exp(2x)/12+exp(-x)/3=cosh(2x)/2+exp(2x)/6+exp(-x)/3; a(n)=(-2)^n/4+5*2^n/12+(-1)^n/3.

CROSSREFS

Sequence in context: A165674 A027446 A027516 * A113955 A110165 A111965

Adjacent sequences:  A092805 A092806 A092807 * A092809 A092810 A092811

KEYWORD

easy,nonn

AUTHOR

Paul Barry, Mar 10 2004

STATUS

approved

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Last modified August 21 00:43 EDT 2017. Contains 290855 sequences.