A037508 Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 1,2,0.

1, 9, 63, 442, 3096, 21672, 151705, 1061937, 7433559, 52034914, 364244400, 2549710800, 17847975601, 124935829209, 874550804463, 6121855631242, 42852989418696, 299970925930872, 2099796481516105

Offset

1,2

Links

Table of n, a(n) for n=1..19.

Index entries for linear recurrences with constant coefficients, signature (7,0,1,-7).

Index entries for 7-automatic sequences.

Formula

G.f.: x*(1+2*x) / ( (x-1)*(7*x-1)*(1+x+x^2) ). - R. J. Mathar, Apr 27 2015

Prog

(PARI) a(n)=([0, 1, 0, 0; 0, 0, 1, 0; 0, 0, 0, 1; -7, 1, 0, 7]^(n-1)*[1; 9; 63; 442])[1, 1] \\ Charles R Greathouse IV, Feb 13 2017

Crossrefs

Cf. A007093, A037511.

Sequence in context: A339786 A201885 A225964 * A037691 A206816 A336670

Adjacent sequences: A037505 A037506 A037507 * A037509 A037510 A037511

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved