cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A320612 Number of parts in all partitions of n in which no part occurs more than nine times.

Original entry on oeis.org

1, 3, 6, 12, 20, 35, 54, 86, 128, 182, 264, 376, 520, 718, 978, 1318, 1761, 2338, 3070, 4008, 5206, 6707, 8604, 10982, 13933, 17604, 22155, 27745, 34627, 43061, 53338, 65859, 81074, 99458, 121687, 148469, 180633, 219202, 265386, 320473, 386147, 464245, 556925
Offset: 1

Views

Author

Alois P. Heinz, Oct 17 2018

Keywords

Crossrefs

Column k=9 of A210485.
Cf. A261776.

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(9*i*(i+1)/2 [0, l[1]*j]+l)(b(n-i*j, min(n-i*j, i-1))), j=0..min(n/i, 9))))
        end:
    a:= n-> b(n$2)[2]:
    seq(a(n), n=1..50);
  • Mathematica
    Table[Length[  Flatten[Select[IntegerPartitions[n], Max[Tally[#][[All, 2]]] <= 9 &]]], {n, 43}] (* Robert Price, Jul 31 2020 *)

Formula

a(n) ~ log(10) * exp(Pi*sqrt(3*n/5)) / (2 * Pi * 15^(1/4) * n^(1/4)). - Vaclav Kotesovec, Oct 18 2018

A185350 Number of parts in all partitions of n in which no part occurs more than twice.

Original entry on oeis.org

0, 1, 3, 3, 8, 11, 17, 23, 36, 48, 69, 88, 125, 157, 212, 271, 356, 445, 574, 711, 906, 1118, 1400, 1711, 2125, 2583, 3171, 3828, 4666, 5604, 6777, 8095, 9730, 11567, 13815, 16357, 19429, 22910, 27077, 31801, 37432, 43802, 51338, 59871, 69914, 81273, 94562
Offset: 0

Views

Author

Alois P. Heinz, Jan 21 2013

Keywords

Examples

			a(6) = 17: [6], [5,1], [4,2], [3,3], [4,1,1], [3,2,1], [2,2,1,1].
a(7) = 23: [7], [6,1], [5,2], [4,3], [5,1,1], [4,2,1], [3,3,1], [3,2,2], [3,2,1,1].
		

Crossrefs

Column k=2 of A210485.

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(i<1, [0, 0],
          add((l->[l[1], l[2]+l[1]*j])(b(n-i*j, i-1)), j=0..min(n/i, 2))))
        end:
    a:= n-> b(n, n)[2]:
    seq(a(n), n=0..50);
  • Mathematica
    b[n_, i_, k_] := b[n, i, k] = If[n==0, {1, 0}, If[i<1, {0, 0}, Sum[b[n - i j, i - 1, k] /. l_List :> {l[[1]], l[[2]] + l[[1]] j}, {j, 0, Min[n/i, k]} ] ] ];
    a[n_] := b[n, n, 2][[2]];
    a /@ Range[0, 50] (* Jean-François Alcover, Dec 10 2020, after Alois P. Heinz *)
    Table[Length[Flatten[Select[IntegerPartitions[n],Max[Length/@Split[#]]<3&]]],{n,0,50}] (* Harvey P. Dale, Jul 04 2023 *)

Formula

a(n) = Sum_{k>=0} k*A209318(n,k).
a(n) ~ log(3) * exp(2*Pi*sqrt(n)/3) / (2*Pi*n^(1/4)). - Vaclav Kotesovec, May 26 2018

A320613 Number of parts in all partitions of n in which no part occurs more than ten times.

Original entry on oeis.org

1, 3, 6, 12, 20, 35, 54, 86, 128, 192, 264, 387, 531, 741, 1001, 1366, 1809, 2425, 3170, 4172, 5398, 6997, 8948, 11482, 14547, 18451, 23193, 29157, 36355, 45347, 56150, 69509, 85565, 105216, 128732, 157393, 191545, 232870, 282033, 341164, 411251, 495197, 594369
Offset: 1

Views

Author

Alois P. Heinz, Oct 17 2018

Keywords

Crossrefs

Column k=10 of A210485.

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, [1, 0], `if`(5*i*(i+1) [0, l[1]*j]+l)(b(n-i*j, min(n-i*j, i-1))), j=0..min(n/i, 10))))
        end:
    a:= n-> b(n$2)[2]:
    seq(a(n), n=1..50);
  • Mathematica
    Table[Length[Flatten[Select[IntegerPartitions[n], Max[Tally[#][[All, 2]]] <= 10 &]]], {n, 43}] (* Robert Price, Jul 31 2020 *)

Formula

a(n) ~ 3^(1/4) * log(11) * exp(2*Pi*sqrt(5*n/33)) / (2 * Pi * 55^(1/4) * n^(1/4)). - Vaclav Kotesovec, Oct 18 2018

A364245 Number of parts in all partitions of 2n into parts with multiplicity <= n.

Original entry on oeis.org

0, 1, 8, 24, 65, 150, 330, 657, 1274, 2338, 4172, 7203, 12171, 20045, 32474, 51623, 80867, 124841, 190406, 286857, 427758, 631367, 923544, 1339226, 1926798, 2751094, 3900931, 5494411, 7690923, 10701618, 14808183, 20380969, 27910066, 38035633, 51597166, 69685656
Offset: 0

Views

Author

Alois P. Heinz, Jul 15 2023

Keywords

Examples

			a(2) = 8 = 3 + 2 + 2 + 1: [2,1,1], [2,2], [3,1], [4].
		

Crossrefs

Programs

  • Maple
    a:= proc(k) option remember; local b; b:=
          proc(n, i) option remember; `if`(n=0, [1, 0], `if`(i<1, 0,
            add((l-> l+[0, l[1]*j])(b(n-i*j, i-1)), j=0..min(n/i, k))))
          end: b(2*k$2)[2]
        end:
    seq(a(n), n=0..37);

Formula

a(n) = A210485(2n,n).
Previous Showing 11-14 of 14 results.