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A196731
Expansion of (1-x)/(1-12*x).
2
1, 11, 132, 1584, 19008, 228096, 2737152, 32845824, 394149888, 4729798656, 56757583872, 681091006464, 8173092077568, 98077104930816, 1176925259169792, 14123103110037504, 169477237320450048
OFFSET
0,2
FORMULA
a(n) = Sum_{k=0..n} A193722(n,k)*9^(n-k).
a(n+1) = 12*a(n) for n > 0. - M. F. Hasler, Oct 05 2011
MATHEMATICA
Join[{1}, NestList[12#&, 11, 20]] (* Harvey P. Dale, Sep 19 2018 *)
PROG
(PARI) a(n)=if(n, 11*12^n--, 1) \\ Charles R Greathouse IV, Oct 05 2011
(PARI) a(n)=(11+!n)*12^(n-1) \\ M. F. Hasler, Oct 05 2011
KEYWORD
nonn,easy
AUTHOR
Philippe Deléham, Oct 05 2011
STATUS
approved