A369502
Expansion of (1/x) * Series_Reversion( x / ((1+x)^2+x)^2 ).
Original entry on oeis.org
1, 6, 47, 420, 4059, 41316, 436345, 4737018, 52535950, 592667532, 6779699073, 78458218746, 916886214115, 10805128064100, 128260666769895, 1532180536574580, 18405744106135914, 222204347510440092, 2694506677864591810, 32804976554127379680, 400837173223351237295
Offset: 0
-
my(N=30, x='x+O('x^N)); Vec(serreverse(x/((1+x)^2+x)^2)/x)
-
a(n) = sum(k=0, n, binomial(2*n+2, k)*binomial(4*n-2*k+4, n-k))/(n+1);
A369504
Expansion of (1/x) * Series_Reversion( x / ((1+x)^2+x^3)^2 ).
Original entry on oeis.org
1, 4, 22, 142, 1005, 7546, 59033, 475962, 3927204, 33001024, 281449964, 2429922400, 21196031340, 186521336460, 1653830553417, 14761130834428, 132516050272100, 1195778542160992, 10839917478886459, 98671228898404032, 901509955793840923
Offset: 0
-
my(N=30, x='x+O('x^N)); Vec(serreverse(x/((1+x)^2+x^3)^2)/x)
-
a(n) = sum(k=0, n\3, binomial(2*n+2, k)*binomial(4*n-2*k+4, n-3*k))/(n+1);
A369506
Expansion of (1/x) * Series_Reversion( x / ((1+x)^3+x^2)^2 ).
Original entry on oeis.org
1, 6, 53, 548, 6192, 74074, 922142, 11822082, 155024190, 2069570934, 28033435791, 384329462490, 5322745393480, 74357950874850, 1046564375245893, 14826433687124098, 211251475010201934, 3025331234242178508, 43523061969049245589, 628692982662691174722
Offset: 0
-
my(N=30, x='x+O('x^N)); Vec(serreverse(x/((1+x)^3+x^2)^2)/x)
-
a(n) = sum(k=0, n\2, binomial(2*n+2, k)*binomial(6*n-3*k+6, n-2*k))/(n+1);
Showing 1-3 of 3 results.