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A016248
Expansion of 1/((1-x)(1-6x)(1-12x)).
0
1, 19, 271, 3511, 43687, 533575, 6458887, 77842567, 936126343, 11245609351, 135019871623, 1620673815943, 19450697930119, 233424047994247, 2801182612927879, 33614755577116039, 403380452257281415
OFFSET
0,2
FORMULA
a(0)=1, a(1)=19, a(n)=18*a(n-1)-72*a(n-2)+1. - Vincenzo Librandi, Feb 10 2011
a(n) = (5*12^(n+2) - 11*6^(n+2) + 6)/330. [Yahia Kahloune, Aug 13 2013]
MAPLE
a:=n->sum((12^(n-j)-6^(n-j))/6, j=0..n): seq(a(n), n=1..17); # Zerinvary Lajos, Jan 12 2007
PROG
(PARI) a(n) = (5*12^(n+2) - 11*6^(n+2) + 6)/330; \\ Joerg Arndt, Aug 13 2013
CROSSREFS
Sequence in context: A139739 A016189 A125476 * A322539 A199819 A016187
KEYWORD
nonn,easy
AUTHOR
STATUS
approved