A292745
Number A(n,k) of partitions of n with k sorts of part 1 which are introduced in ascending order; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
1, 1, 0, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 2, 1, 1, 3, 6, 5, 2, 1, 1, 3, 7, 13, 7, 4, 1, 1, 3, 7, 19, 26, 11, 4, 1, 1, 3, 7, 20, 52, 54, 15, 7, 1, 1, 3, 7, 20, 62, 151, 108, 22, 8, 1, 1, 3, 7, 20, 63, 217, 442, 219, 30, 12, 1, 1, 3, 7, 20, 63, 232, 803, 1314, 439, 42, 14
Offset: 0
A(3,2) = 6: 3, 21a, 1a1a1a, 1a1a1b, 1a1b1a, 1a1b1b.
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, 1, 1, 1, ...
0, 1, 1, 1, 1, 1, 1, 1, 1, ...
1, 2, 3, 3, 3, 3, 3, 3, 3, ...
1, 3, 6, 7, 7, 7, 7, 7, 7, ...
2, 5, 13, 19, 20, 20, 20, 20, 20, ...
2, 7, 26, 52, 62, 63, 63, 63, 63, ...
4, 11, 54, 151, 217, 232, 233, 233, 233, ...
4, 15, 108, 442, 803, 944, 965, 966, 966, ...
7, 22, 219, 1314, 3092, 4158, 4425, 4453, 4454, ...
Columns k=0-10 give:
A002865,
A000041,
A320733,
A320734,
A320735,
A320736,
A320737,
A320738,
A320739,
A320740,
A320741.
-
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, k)-> b(n$2, k):
seq(seq(A(n, d-n), n=0..d), d=0..14);
-
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_, k_] := b[n, n, k];
Table[A[n, d - n], {d, 0, 14}, {n, 0, d}] // Flatten (* Jean-François Alcover, May 17 2018, translated from Maple *)
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 *)
A259401
a(n) = Sum_{k=0..n} 2^(n-k)*p(k), where p(k) is the partition function A000041.
Original entry on oeis.org
1, 3, 8, 19, 43, 93, 197, 409, 840, 1710, 3462, 6980, 14037, 28175, 56485, 113146, 226523, 453343, 907071, 1814632, 3629891, 7260574, 14522150, 29045555, 58092685, 116187328, 232377092, 464757194, 929518106, 1859040777, 3718087158, 7436181158, 14872370665
Offset: 0
-
a:= proc(n) option remember; `if`(n<0, 0,
2*a(n-1)+combinat[numbpart](n))
end:
seq(a(n), n=0..32); # Alois P. Heinz, Dec 03 2019
-
Table[Sum[2^(n-k)*PartitionsP[k],{k,0,n}],{n,0,50}]
-
a(n) = sum(k=0, n, 2^(n-k)*numbpart(k)); \\ Michel Marcus, Dec 03 2019
A292747
Number of partitions of 2n with exactly n kinds of 1's which are introduced in ascending order.
Original entry on oeis.org
1, 1, 8, 97, 1778, 43747, 1349703, 50033463, 2164920950, 107074391802, 5957871478583, 368330684797595, 25046735249606820, 1857906353180702199, 149289720057575358424, 12917953683720554797237, 1197556745092101849164899, 118414507831659267311128558
Offset: 0
a(2) = 8: 21a1b, 1a1a1a1b, 1a1a1b1a, 1a1a1b1b, 1a1b1a1a, 1a1b1a1b, 1a1b1b1a, 1a1b1b1b (the two kinds of 1's are denoted by 1a and 1b).
-
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(2*n$2, n)-b(2*n$2, n-1):
seq(a(n), n=0..20);
-
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[2n, 2n, n] - b[2n, 2n, n-1];
a /@ Range[0, 20] (* Jean-François Alcover, Dec 12 2020, after Alois P. Heinz *)
A320816
Number of partitions of n with exactly three sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 6, 26, 97, 334, 1095, 3482, 10855, 33405, 101925, 309237, 934691, 2818110, 8482505, 25504000, 76625146, 230101961, 690759226, 2073184749, 6221368879, 18667736528, 56010470158, 168045932624, 504166843427, 1512558622966, 4537792056226, 13613608545770
Offset: 3
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(3):
seq(a(n), n=3..35);
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i < 2, Sum[StirlingS2[n, j], {j, 0, k}], Sum[b[n - i*j, i - 1, k], {j, 0, n/i}]];
a[n_] := With[{k = 3}, b[n, n, k] - b[n, n, k - 1]];
a /@ Range[3, 35] (* Jean-François Alcover, Dec 16 2020, after Alois P. Heinz *)
A320817
Number of partitions of n with exactly four sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 10, 66, 361, 1778, 8207, 36310, 156095, 657785, 2733065, 11241497, 45900679, 186420826, 754165809, 3042167236, 12245294090, 49211278321, 197535872510, 792216674789, 3175088068035, 12719020008668, 50932090504830, 203896407951944, 816089798651203
Offset: 4
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(4):
seq(a(n), n=4..35);
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i < 2, Sum[StirlingS2[n, j], {j, 0, k}], Sum[b[n - i*j, i - 1, k], {j, 0, n/i}]];
a[n_] := With[{k = 4}, b[n, n, k] - b[n, n, k-1]];
a /@ Range[4, 35] (* Jean-François Alcover, Dec 17 2020, after Alois P. Heinz *)
A320818
Number of partitions of n with exactly five sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 15, 141, 1066, 7108, 43747, 255045, 1431320, 7814385, 41804990, 220266447, 1147232914, 5922585396, 30367092789, 154877631181, 786633449995, 3982378528296, 20109428513990, 101339359244739, 509871884291730, 2562078441467318, 12861324297841420
Offset: 5
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(5):
seq(a(n), n=5..35);
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i < 2, Sum[StirlingS2[n, j], {j, 0, k}], Sum[b[n - i*j, i - 1, k], {j, 0, n/i}]];
a[n_] := With[{k = 5}, b[n, n, k] - b[n, n, k - 1]];
a /@ Range[5, 35] (* Jean-François Alcover, Dec 17 2020, after Alois P. Heinz *)
A320819
Number of partitions of n with exactly six sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 21, 267, 2668, 23116, 182443, 1349703, 9529538, 64991613, 431754668, 2810794455, 18011999644, 113994583260, 714334592349, 4440885185275, 27431944561645, 168574045898166, 1031553703902986, 6290661582662655, 38253841380267660, 232085126723073278
Offset: 6
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(6):
seq(a(n), n=6..35);
A320820
Number of partitions of n with exactly seven sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 28, 463, 5909, 64479, 633796, 5786275, 50033463, 415225854, 3338335646, 26179143977, 201266007483, 1522856635641, 11374331041836, 84061202478127, 615860361908534, 4479596579257904, 32388729758708314, 233011769893620853, 1669336230635613631
Offset: 7
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(7):
seq(a(n), n=7..35);
A320821
Number of partitions of n with exactly eight sorts of part 1 which are introduced in ascending order.
Original entry on oeis.org
1, 36, 751, 11917, 159815, 1912316, 21084803, 218711887, 2164920950, 20657703246, 191440769945, 1732792167043, 15385193971985, 134455882817716, 1159708265019855, 9893526482067374, 83627808435796896, 701411197245083482, 5844301347854288709, 48423747013469923303
Offset: 8
-
b:= proc(n, i, k) option remember; `if`(n=0 or i<2, add(
Stirling2(n, j), j=0..k), add(b(n-i*j, i-1, k), j=0..n/i))
end:
a:= n-> (k-> b(n$2, k)-b(n$2, k-1))(8):
seq(a(n), n=8..35);
Showing 1-10 of 12 results.
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