A037642 Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 2,3,1.

2, 17, 120, 842, 5897, 41280, 288962, 2022737, 14159160, 99114122, 693798857, 4856592000, 33996144002, 237973008017, 1665811056120, 11660677392842, 81624741749897, 571373192249280, 3999612345744962

Offset

1,1

Links

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

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

Formula

G.f.: x*(x+2)*(1+x) / ( (x-1)*(7*x-1)*(1+x+x^2) ). - R. J. Mathar, Nov 21 2011

Mathematica

Module[{nn=20, p}, p=PadRight[{}, nn, {2, 3, 1}]; Table[FromDigits[Take[p, n], 7], {n, nn}]] (* or *) LinearRecurrence[{7, 0, 1, -7}, {2, 17, 120, 842}, 20] (* Harvey P. Dale, Jul 17 2013 *)

Crossrefs

Sequence in context: A037747 A037628 A037754 * A161128 A220403 A097716

Adjacent sequences: A037639 A037640 A037641 * A037643 A037644 A037645

Keyword

nonn,base

Author

Clark Kimberling

Status

approved