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Largest terms a(n) forming a self-convolution of an integer sequence (A132832) such that: a(n) <= 2*a(n-1) for n>0 with a(0)=1.
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%I #2 Mar 30 2012 18:37:04

%S 1,2,3,6,11,22,44,88,175,350,700,1400,2799,5598,11195,22390,44779,

%T 89558,179115,358230,716459,1432918,2865835,5731670,11463340,22926680,

%U 45853360,91706720,183413439,366826878,733653755,1467307510,2934615019

%N Largest terms a(n) forming a self-convolution of an integer sequence (A132832) such that: a(n) <= 2*a(n-1) for n>0 with a(0)=1.

%C a(n) ~ 2^n*c where c=0.683268303731665578137197731736227240453607...

%o (PARI) {a(n)=local(B=[1],t);if(n==0,1,for(k=1,n,t=2*a(k-1);B=concat(B,t); B[ #B]=t+1-denominator(Vec(Ser(B)^(1/2))[ #B]) ));B[n+1]}

%Y Cf. A132832.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Sep 07 2007