A292463
Number of partitions of n with n kinds of 1.
Original entry on oeis.org
1, 1, 4, 14, 51, 188, 702, 2644, 10026, 38223, 146359, 562456, 2168134, 8379539, 32459199, 125984039, 489837300, 1907490728, 7438346255, 29042470132, 113522618066, 444199913556, 1739735079466, 6819657196928, 26753893533257, 105034060120469, 412637434996367
Offset: 0
a(2) = 4: 2, 1a1a, 1a1b, 1b1b.
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2,
binomial(k+n-1, n), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> b(n$3):
seq(a(n), n=0..30);
# second Maple program:
b:= proc(n, k) option remember; `if`(n=0, 1, add(
(numtheory[sigma](j)+k-1)*b(n-j, k), j=1..n)/n)
end:
a:= n-> b(n$2):
seq(a(n), n=0..30);
# third Maple program:
b:= proc(n, k) option remember; `if`(n=0, 1, `if`(k=1,
combinat[numbpart](n), b(n-1, k) +b(n, k-1)))
end:
a:= n-> b(n$2):
seq(a(n), n=0..30);
-
Table[SeriesCoefficient[1/(1-x)^(n-1) * Product[1/(1-x^k), {k,1,n}], {x,0,n}], {n,0,30}] (* Vaclav Kotesovec, Sep 19 2017 *)
A292503
Number of partitions of n with n sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 1, 3, 7, 20, 63, 233, 966, 4454, 22404, 121616, 706362, 4361977, 28494493, 196087988, 1416515642, 10709058487, 84505818259, 694397612486, 5929368380664, 52513737017847, 481577858196052, 4565851595293151, 44692014464166068, 451058715629365617
Offset: 0
a(2) = 3: 2, 1a1a, 1a1b.
a(3) = 7: 3, 21a, 1a1a1a, 1a1a1b, 1a1b1a, 1a1b1b, 1a1b1c.
-
f:= (n, k)-> add(Stirling2(n, j), j=0..k):
b:= proc(n, i, k) option remember; `if`(n=0 or i<2,
f(n, k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> b(n$3):
seq(a(n), n=0..30);
-
f[n_, k_] := Sum[StirlingS2[n, j], {j, 0, k}];
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i < 2, f[n, k], Sum[b[n - i*j, i - 1, k], {j, 0, n/i}]];
a[n_] := b[n, n, n];
Table[a[n], {n, 0, 30}] (* Jean-François Alcover, May 17 2018, translated from Maple *)
A292741
Number A(n,k) of partitions of n with k sorts of part 1; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
1, 1, 0, 1, 1, 1, 1, 2, 2, 1, 1, 3, 5, 3, 2, 1, 4, 10, 11, 5, 2, 1, 5, 17, 31, 24, 7, 4, 1, 6, 26, 69, 95, 50, 11, 4, 1, 7, 37, 131, 278, 287, 104, 15, 7, 1, 8, 50, 223, 657, 1114, 865, 212, 22, 8, 1, 9, 65, 351, 1340, 3287, 4460, 2599, 431, 30, 12, 1, 10, 82, 521, 2459, 8042, 16439, 17844, 7804, 870, 42, 14
Offset: 0
A(1,3) = 3: 1a, 1b, 1c.
A(2,3) = 10: 2, 1a1a, 1a1b, 1a1c, 1b1a, 1b1b, 1b1c, 1c1a, 1c1b, 1c1c.
A(3,2) = 11: 3, 21a, 21b, 1a1a1a, 1a1a1b, 1a1b1a, 1a1b1b, 1b1a1a, 1b1a1b, 1b1b1a, 1b1b1b.
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, 1, 1, ...
0, 1, 2, 3, 4, 5, 6, 7, ...
1, 2, 5, 10, 17, 26, 37, 50, ...
1, 3, 11, 31, 69, 131, 223, 351, ...
2, 5, 24, 95, 278, 657, 1340, 2459, ...
2, 7, 50, 287, 1114, 3287, 8042, 17215, ...
4, 11, 104, 865, 4460, 16439, 48256, 120509, ...
4, 15, 212, 2599, 17844, 82199, 289540, 843567, ...
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, k^n,
add(b(n-i*j, i-1, k), j=0..iquo(n, i)))
end:
A:= (n, k)-> b(n$2, k):
seq(seq(A(n, d-n), n=0..d), d=0..14);
-
b[0, , ] = 1; b[n_, i_, k_] := b[n, i, k] = If[i < 2, k^n, Sum[b[n - i*j, i - 1, k], {j, 0, Quotient[n, i]}]];
A[n_, k_] := b[n, n, k];
Table[A[n, d - n], {d, 0, 14}, {n, 0, d}] // Flatten (* Jean-François Alcover, May 19 2018, translated from Maple *)
A292507
Number of partitions of n with up to n distinct kinds of 1.
Original entry on oeis.org
1, 1, 2, 5, 13, 33, 82, 201, 488, 1176, 2817, 6714, 15931, 37647, 88628, 207914, 486158, 1133304, 2634339, 6106953, 14121157, 32573842, 74968044, 172164086, 394561089, 902471184, 2060338222, 4695324425, 10681885697, 24261437446, 55017434305, 124573678280
Offset: 0
a(3) = 5: 3, 21a, 21b, 21c, 1a1b1c.
a(4) = 13: 4, 31a, 31b, 31c, 31d, 22, 21a1b, 21a1c, 21a1d, 21b1c, 21b1d, 21c1d, 1a1b1c1d.
-
b:= proc(n, i, k) option remember; `if`(n=0 or i=1,
binomial(k, n), `if`(i>n, 0, b(n-i, i, k))+b(n, i-1, k))
end:
a:= n-> b(n$3):
seq(a(n), n=0..35);
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i == 1, Binomial[k, n], If[i > n, 0, b[n - i, i, k]] + b[n, i - 1, k]];
a[n_] := b[n, n, n];
Table[a[n], {n, 0, 35}] (* Jean-François Alcover, May 20 2018, translated from Maple *)
A292567
a(n) = [x^n] 1/(1+n*x) * Product_{j=2..n} 1/(1-x^j).
Original entry on oeis.org
1, -1, 5, -29, 270, -3233, 47800, -838561, 17013991, -391779640, 10091836632, -287491284748, 8973657413421, -304549220113387, 11165193890312790, -439726629957500944, 18514829984975265703, -829953080825411342745, 39461813340364709540008
Offset: 0
-
b:= proc(n, i, k) option remember; `if`(n=0 or i=1, (-k)^n,
`if`(i>n, 0, b(n-i, i, k))+b(n, i-1, k))
end:
a:= n-> b(n$3):
seq(a(n), n=0..23);
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i == 1, (-k)^n, If[i > n, 0, b[n - i, i, k]] + b[n, i - 1, k]];
a[n_] := If[n == 0, 1, b[n, n, n]];
a /@ Range[0, 23] (* Jean-François Alcover, Dec 30 2020, after Alois P. Heinz *)
Showing 1-5 of 5 results.