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A144577 Numerators of expansion of exp(1-sqrt(1-x-2*x^2)). 2

%I #13 Dec 17 2020 20:39:56

%S 1,1,5,55,757,4973,194671,842411,11218933,3358395757,115106092471,

%T 2189182968473,7379994323497,1699615680368861,19346973713722411,

%U 23008945996332629551,1335947317588460238301,8289679255721758160317,1095056665754286849584771

%N Numerators of expansion of exp(1-sqrt(1-x-2*x^2)).

%H Robert Israel, <a href="/A144577/b144577.txt">Table of n, a(n) for n = 0..367</a>

%F A144577/A144578 is D-finite with recurrence 64*b(n) + 48*b(n+1) + (32*n^2 + 96*n + 76)*b(n+2) + (24*n^2 + 120*n + 145)*b(n+3) + (-12*n^2 - 66*n - 72)*b(n+4) + (-4*n^2 - 36*n - 80)*b(n+5)=0. - _Robert Israel_, Feb 07 2019

%e 1 + (1/2)*x + (5/4)*x^2 + (55/48)*x^3 + (757/384)*x^4 + (4973/1920)*x^5 + (...

%p S:= series(exp(1-sqrt(1-x-2*x^2),x,31):

%p seq(numer(coeff(S,x,n)),n=0..30); # _Robert Israel_, Feb 07 2019

%Y Cf. A144578.

%K nonn,frac

%O 0,3

%A _N. J. A. Sloane_, Jan 07 2009

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Last modified May 28 04:05 EDT 2023. Contains 362992 sequences. (Running on oeis4.)