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%I #19 Sep 20 2018 02:57:47
%S 1,1,1,1,2,6,26,151,1093,9489,96084,1111722,14469388,209234595,
%T 3328056991,57746229265,1085448899206,21972175778646,476535125344462,
%U 11024061833485335,270965694793159153,7051933526740491393,193723061625591928384,5601822117610355927946
%N Shifts left 3 places under "CIJ" (necklace, indistinct, labeled) transform.
%H Andrew Howroyd, <a href="/A032187/b032187.txt">Table of n, a(n) for n = 1..200</a>
%F a(n) = sum(k=0..n-5, binomial(n-4,k)*a(k+4)*a(n-k-4)) + a(n-3), n>4, a(1)=a(2)=a(3)=a(4)=1. - _Vladimir Kruchinin_, May 10 2011
%F E.g.f. A(x) satisfies differential equation A'''(x)=log(1/(1-A(x))), A'(0)=1, A''(0)=1, A'''(0)=1. - _Vladimir Kruchinin_, Nov 19 2011
%o (Maxima)
%o a(n):=if n=0 then 0 else if n<5 then 1 else sum(binomial(n-4,k)*a(k+4)*a(n-k-4),k,0,n-5)+a(n-3); /* _Vladimir Kruchinin_, May 10 2011 */
%o (PARI)
%o CIJ(p)={-log(1-p)}
%o seq(n)={my(p=x+x^2+O(x*x^(n%3))); for(i=1, n\3, p=intformal(1 + intformal(1 + intformal(1 + CIJ(p))))); Vec(serlaplace(p))} \\ _Andrew Howroyd_, Sep 19 2018
%K nonn,eigen
%O 1,5
%A _Christian G. Bower_
%E Terms a(22) and beyond from _Andrew Howroyd_, Sep 19 2018
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