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A196661
Expansion of (1-2x)/(1-7x).
5
1, 5, 35, 245, 1715, 12005, 84035, 588245, 4117715, 28824005, 201768035, 1412376245, 9886633715, 69206436005, 484445052035, 3391115364245, 23737807549715, 166164652848005, 1163152569936035, 8142067989552245, 56994475926865715, 398961331488060005
OFFSET
0,2
FORMULA
a(0) = 1, a(n) = 5*7^(n-1) for n>0.
a(n) = Sum_{k=0..n} A193722(n,k)*2^k.
PROG
(PARI) a(n)=if(n, 5*7^(n-1), 1) \\ Charles R Greathouse IV, Nov 21 2011
CROSSREFS
Cf. A002001, A193722, A193577 (which is the same except for the initial 1).
Sequence in context: A155127 A239846 A193577 * A104532 A292839 A180900
KEYWORD
nonn,easy
AUTHOR
Philippe Deléham, Oct 05 2011
STATUS
approved