A037649 Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 3,0,1.

3, 21, 148, 1039, 7273, 50912, 356387, 2494709, 17462964, 122240751, 855685257, 5989796800, 41928577603, 293500043221, 2054500302548, 14381502117839, 100670514824873, 704693603774112, 4932855226418787

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..200

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

Formula

a(n) = 7*a(n-1)+a(n-3)-7*a(n-4). G.f.: x*(x^2+3) / ((x-1)*(7*x-1)*(x^2+x+1)). - Colin Barker, Aug 09 2014

Mathematica

Module[{nn=20, c}, c=PadRight[{}, nn, {3, 0, 1}]; Table[FromDigits[Take[c, n], 7], {n, nn}]] (* Harvey P. Dale, Aug 09 2014 *)

Crossrefs

Sequence in context: A206638 A357652 A037761 * A037768 A037656 A074577

Adjacent sequences: A037646 A037647 A037648 * A037650 A037651 A037652

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved