A369124
Expansion of (1/x) * Series_Reversion( x * ((1-x)^4+x^4) ).
Original entry on oeis.org
1, 4, 26, 204, 1770, 16352, 157696, 1569096, 15988652, 165998624, 1749696208, 18673883696, 201394693864, 2191421381632, 24028822589440, 265238416143584, 2944999336948944, 32869042668479424, 368551132961138784, 4149643380825661824, 46897527236429235520
Offset: 0
-
my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^4+x^4))/x)
-
a(n) = sum(k=0, n\4, (-1)^k*binomial(n+k, k)*binomial(5*n+3, n-4*k))/(n+1);
A368011
Expansion of (1/x) * Series_Reversion( x * ((1-x)^5-x^5) ).
Original entry on oeis.org
1, 5, 40, 385, 4095, 46377, 548380, 6691620, 83637450, 1065311665, 13777916774, 180451354720, 2388503030675, 31900445734050, 429369814375480, 5818270533841408, 79309912829992350, 1086768622818959100, 14961519902879613700, 206839961042385226110
Offset: 0
-
my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^5-x^5))/x)
-
a(n) = sum(k=0, n\5, binomial(n+k, k)*binomial(6*n+4, n-5*k))/(n+1);
A369123
Expansion of (1/x) * Series_Reversion( x * ((1-x)^2+x^2) ).
Original entry on oeis.org
1, 2, 6, 20, 68, 224, 672, 1584, 880, -22880, -215072, -1414400, -8012032, -41344000, -198120448, -884348160, -3640426752, -13403384320, -40424947200, -65476561920, 329862128640, 4603911045120, 35276325027840, 221747978649600, 1244854463643648
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\2, (-1)^k*binomial(n+k, k)*binomial(3*n+1, n-2*k))/(n+1);
Showing 1-3 of 3 results.