

A022321


a(n) = a(n1) + a(n2) + 1, with a(0) = 1 and a(1) = 7.


1



1, 7, 9, 17, 27, 45, 73, 119, 193, 313, 507, 821, 1329, 2151, 3481, 5633, 9115, 14749, 23865, 38615, 62481, 101097, 163579, 264677, 428257, 692935, 1121193, 1814129, 2935323, 4749453, 7684777, 12434231
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OFFSET

0,2


LINKS



FORMULA

G.f.: (1+5*x5*x^2)/((1x)*(1xx^2)).


MATHEMATICA

a[0]=1; a[1]=7; a[n_]:=a[n]=a[n1]+a[n2]+1; Table[a[n], {n, 0, 40}] (* Harvey P. Dale, Jan 23 2011 *)


PROG

(PARI) x='x+O('x^50); Vec((1+5*x5*x^2)/((1x)*(1xx^2))) \\ G. C. Greubel, Aug 25 2017


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



