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A107049 Numerators of coefficients that satisfy: 3^n = Sum_{k=0..n} c(k)*x^k for n>=0, where c(k) = a(k)/A107050(k).

%I A107049 #4 Mar 30 2012 18:36:46
%S A107049 1,2,1,11,101,71723,1462111,194269981673,224103520039487,
%T A107049 14876670160046176873,20871062802926443547323,
%U A107049 606768727432357137728440774281877,97827345788163051844748893917483101
%N A107049 Numerators of coefficients that satisfy: 3^n = Sum_{k=0..n} c(k)*x^k for n>=0, where c(k) = a(k)/A107050(k).
%C A107049 Sum_{k>=0} a(k)/A107050(k) = 4.5568226185870666883519278484116281050682807568451524897...
%F A107049 a(n)/A107050(n) = Sum_{k=0..n} T(n, k)*3^k where T(n, k) = A107045(n, k)/A107046(n, k) = [A079901^-1](n, k) (matrix inverse of A079901).
%e A107049 3^0 = 1;
%e A107049 3^1 = 1 + (2)*1;
%e A107049 3^2 = 1 + (2)*2 + (1)*2^2;
%e A107049 3^3 = 1 + (2)*3 + (1)*3^2 + (11/27)*3^3;
%e A107049 3^4 = 1 + (2)*4 + (1)*4^2 + (11/27)*4^3 + (101/864)*4^4.
%e A107049 Initial coefficients are:
%e A107049 A107049/A107050 = {1, 2, 1, 11/27, 101/864, 71723/2700000,
%e A107049 1462111/291600000, 194269981673/240145138800000,
%e A107049 224103520039487/1967268977049600000, ...}.
%o A107049 (PARI) {a(n)=numerator(sum(k=0,n,3^k*(matrix(n+1,n+1,r,c,if(r>=c,(r-1)^(c-1)))^-1)[n+1,k+1]))}
%Y A107049 Cf. A107045/A107046, A107047/A107048 (y=2), A107051/A107052 (y=4), A107053/A107054 (y=5).
%K A107049 nonn,frac
%O A107049 0,2
%A A107049 _Paul D. Hanna_, May 10 2005