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Self-convolution 6th power equals A106224, which consists entirely of digits {0,1,2,3,4,5} after the initial terms {1,6}.
4

%I #7 Mar 13 2015 00:04:48

%S 1,1,-2,7,-27,114,-506,2322,-10919,52316,-254369,1251563,-6218656,

%T 31153743,-157167147,797682007,-4069817562,20860266354,-107358128720,

%U 554533772363,-2873667741743,14935575580894,-77833224795929,406595414780038,-2128748177726089,11167899337858904

%N Self-convolution 6th power equals A106224, which consists entirely of digits {0,1,2,3,4,5} after the initial terms {1,6}.

%F Limit a(n+1)/a(n) = -5.502856676359094846755190514140489974645...

%e A(x) = 1 + x - 2*x^2 + 7*x^3 - 27*x^4 + 114*x^5 - 506*x^6 +-...

%e A(x)^6 = 1 + 6*x + 3*x^2 + 2*x^3 + 3*x^4 + 3*x^8 + 4*x^9 +...

%e A106224 = {1,6,3,2,3,0,0,0,3,4,3,0,0,0,3,2,0,0,0,0,3,2,...}.

%o (PARI) {a(n)=local(A=1+6*x);if(n==0,1, for(j=1,n, for(k=0,5,t=polcoeff((A+k*x^j+x*O(x^j))^(1/6),j); if(denominator(t)==1,A=A+k*x^j;break))); return(polcoeff((A+x*O(x^n))^(1/6),n)))}

%Y Cf. A106224, A106219, A106221, A106223, A106227.

%K sign,base

%O 0,3

%A _Paul D. Hanna_, May 01 2005