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 A016230 Expansion of 1/((1-x)(1-5x)(1-7x)). 0

%I

%S 1,13,122,1010,7851,58863,431572,3118660,22318901,158673713,

%T 1122923022,7921496310,55755649951,391815428563,2750337394472,

%U 19290508733960,135224296001001,947523746323413,6637434595845922

%N Expansion of 1/((1-x)(1-5x)(1-7x)).

%F a(0)=1, a(1)=13, a(n)=12*a(n-1)-35*a(n-2)+1. - _Vincenzo Librandi_, Feb 10 2011

%F a(n) = (2*7^(n+2) - 3*5^(n+2) + 1)/24. - _Yahia Kahloune_, Aug 13 2013

%p a:=n->sum((7^(n-j)-5^(n-j))/2,j=0..n): seq(a(n), n=1..19); # _Zerinvary Lajos_, Jan 15 2007

%o (PARI) a(n) = (2*7^(n+2) - 3*5^(n+2) + 1)/24; \\ _Joerg Arndt_, Aug 13 2013

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_

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Last modified November 25 20:07 EST 2020. Contains 338626 sequences. (Running on oeis4.)