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A037614
Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 1,3,2.
0
1, 10, 72, 505, 3538, 24768, 173377, 1213642, 8495496, 59468473, 416279314, 2913955200, 20397686401, 142783804810, 999486633672, 6996406435705, 48974845049938, 342823915349568, 2399767407446977
OFFSET
1,2
FORMULA
G.f.: x*(1+x)*(2*x+1) / ( (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; 10; 72; 505])[1, 1] \\ Charles R Greathouse IV, Feb 13 2017
CROSSREFS
Sequence in context: A164546 A221552 A037712 * A138782 A155606 A181671
KEYWORD
nonn,base,easy
STATUS
approved