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A187064 Coefficients in numerator polynomial of: Sum (k=1 to n) of x^k/(1-x^k).

%I A187064 #13 Jun 11 2014 06:34:56
%S A187064 1,2,1,3,4,3,1,4,5,7,5,3,1,5,11,19,24,26,22,16,9,4,1,6,7,15,18,23,21,
%T A187064 21,15,11,6,3,1,7,15,32,52,77,99,120,128,130,119,102,79,57,36,21,10,4,
%U A187064 1,8,17,36,58,93,125,165,193,220,229,231,213,191,157,124
%N A187064 Coefficients in numerator polynomial of: Sum (k=1 to n) of x^k/(1-x^k).
%C A187064 The number of elements per row begins: 1,2,4,6,10,12,18,... which appears to be A002088.
%C A187064 Row sums begin: 1,3,11,25,137,147,1089,... which appears to be A025529.
%e A187064 Table begins:
%e A187064 1,
%e A187064 2,1,
%e A187064 3,4,3,1,
%e A187064 4,5,7,5,3,1,
%e A187064 5,11,19,24,26,22,16,9,4,1,
%e A187064 6,7,15,18,23,21,21,15,11,6,3,1,
%e A187064 7,15,32,52,77,99,120,128,130,119,102,79,57,36,21,10,4,1,
%e A187064 Polynomials begin:
%e A187064 -(1*x^1)/(x^1-1)
%e A187064 -(2*x^2+1*x)/(x^2-1)
%e A187064 -(3*x^4+4*x^3+3*x^2+1*x^1)/(x^4+x^3-x^1-1)
%e A187064 -(4*x^6+5*x^5+7*x^4+5*x^3+3*x^2+1*x^1)/(x^6+x^5+x^4-x^2-x^1-1)
%o A187064 (PARI) row(n) = v = Vec(numerator(sum(k=1, n, x^k/(1-x^k)))); for (k=1, #v-1, print1(abs(v[k]), ", ")); /*print*/; \\ _Michel Marcus_, Jun 11 2014
%K A187064 nonn,tabf
%O A187064 1,2
%A A187064 _Mats Granvik_, Mar 07 2011
%E A187064 More terms from _Michel Marcus_, Jun 11 2014