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A037553
Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,1.
1
2, 9, 37, 150, 601, 2405, 9622, 38489, 153957, 615830, 2463321, 9853285, 39413142, 157652569, 630610277, 2522441110, 10089764441, 40359057765, 161436231062, 645744924249, 2582979696997, 10331918787990, 41327675151961
OFFSET
1,1
FORMULA
G.f.: x*(2+x+x^2) / ( (x-1)*(4*x-1)*(1+x+x^2) ). - R. J. Mathar, Nov 21 2011
MATHEMATICA
LinearRecurrence[{4, 0, 1, -4}, {2, 9, 37, 150}, 40] (* Vincenzo Librandi, Jun 17 2012 *)
Module[{nn=30, c}, c=PadRight[{}, nn, {2, 1, 1}]; Table[FromDigits[Take[c, n], 4], {n, nn}]] (* Harvey P. Dale, May 06 2015 *)
PROG
(Magma) I:=[2, 9, 37, 150]; [n le 4 select I[n] else 4*Self(n-1)+Self(n-3)-4*Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jun 17 2012
CROSSREFS
Sequence in context: A373910 A373909 A206374 * A178875 A012493 A106851
KEYWORD
nonn,base
STATUS
approved