A367236
G.f. satisfies A(x) = 1 + x / (1 - x*A(x)^2)^2.
Original entry on oeis.org
1, 1, 2, 7, 26, 107, 462, 2074, 9572, 45147, 216638, 1054254, 5190710, 25810064, 129423512, 653740518, 3323270096, 16988894131, 87283137130, 450434292624, 2333851816654, 12136369892776, 63318984098996, 331347363084737, 1738713937163124, 9146850725274636
Offset: 0
-
a(n, s=2, t=0, u=2) = sum(k=0, n, binomial(t*k+u*(n-k)+1, k)*binomial(n+(s-1)*k-1, n-k)/(t*k+u*(n-k)+1));
A367238
G.f. satisfies A(x) = 1 + x*A(x)^3 / (1 - x*A(x)^2)^2.
Original entry on oeis.org
1, 1, 5, 31, 219, 1672, 13439, 112043, 960017, 8402085, 74791408, 675033956, 6163120105, 56820187321, 528231686315, 4946304326883, 46609889424547, 441664236745594, 4205848369345681, 40228631544942031, 386317524696654392, 3723196299965400616
Offset: 0
-
a(n, s=2, t=3, u=2) = sum(k=0, n, binomial(t*k+u*(n-k)+1, k)*binomial(n+(s-1)*k-1, n-k)/(t*k+u*(n-k)+1));
A367282
G.f. satisfies A(x) = 1 + x*A(x)^2 * (1 + x*A(x)^2)^2.
Original entry on oeis.org
1, 1, 4, 18, 94, 527, 3108, 18993, 119214, 763997, 4978304, 32883853, 219690066, 1481858835, 10078051830, 69030877581, 475795428158, 3297527987794, 22965847261928, 160649189379029, 1128201207643744, 7951399289858530, 56222323349767666
Offset: 0
-
a(n, s=2, t=2, u=2) = sum(k=0, n, binomial(t*k+u*(n-k)+1, k)*binomial(s*k, n-k)/(t*k+u*(n-k)+1));
Showing 1-3 of 3 results.