# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a233508 Showing 1-1 of 1 %I A233508 #13 Dec 16 2013 09:46:43 %S A233508 1,1,1,1,3,1,1,3,2,1,1,2,3,5,1,1,5,5,5,3,1,1,3,15,10,15,7,1,1,7,21,35, %T A233508 35,21,4,1,1,4,14,28,35,28,14,9,1,1,9,18,42,63,63,42,18,5,1,1,5,45,60, %U A233508 105,126,105,60,45,11,1 %N A233508 Numerators of the triangle of polynomial coefficients P(0,x)=1, 2*P(n)=(1+x)*((1+x)^(n-1)+x^(n-1)). Of the first array of A133135. %C A233508 Discovered via Euler polynomials A060096(n)/A060097(n). %C A233508 The fractional sequence is 1, 1, 1, 1/2, 3/2, 1, 1/2, 3/2, 2, 1, 1/2, 2, 3, 5/2, 1,... =a(n)/b(n). There is a correspondant sequence for Bernoulli polynomials (*). %F A233508 a(n) = reduced A133138(n)/A007395. %e A233508 1, %e A233508 1, 1, %e A233508 1, 3, 1, %e A233508 1, 3, 2, 1, %e A233508 1, 2, 3, 5, 1, %e A233508 1, 5, 5, 5, 3, 1, etc. %t A233508 p[n_] := (1+x)*((1+x)^(n-1)+x^(n-1))/2; t[n_, k_] := Coefficient[p[n], x, k] // Numerator; Table[t[n, k], {n, 0, 10 }, {k, 0, n}] // Flatten (* _Jean-François Alcover_, Dec 16 2013 *) %Y A233508 Cf. (*) A193815. %K A233508 nonn,tabl,frac %O A233508 0,5 %A A233508 _Paul Curtz_, Dec 11 2013 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE