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.

Showing 1-6 of 6 results.

A237278 Numbers k such that A000041(k) == 0 (mod 4).

Original entry on oeis.org

11, 15, 21, 26, 30, 55, 58, 59, 62, 66, 70, 74, 75, 78, 80, 84, 94, 96, 98, 100, 106, 108, 109, 112, 113, 116, 117, 120, 122, 124, 125, 126, 128, 130, 131, 133, 135, 136, 137, 141, 142, 149, 153, 154, 171, 179, 180, 187, 191, 200, 205, 206, 230, 231, 236
Offset: 1

Views

Author

Clark Kimberling, Feb 05 2014

Keywords

Comments

The set of positive integers is partitioned by the sequences A237278-A237281.

Examples

			A000041(11) = 56 == 0 (mod 4).
		

Crossrefs

Cf. A000041, A237276, A237279, A237280, A237281, A243935 (see crossrefs).
Cf. A121062.

Programs

  • Mathematica
    f[n_, k_] := Select[Range[250], Mod[PartitionsP[#], n] == k &]
    Table[f[4, k], {k, 0, 3}] (* A237278-A237281 *)
  • PARI
    is(n)=numbpart(n)%4==0 \\ Charles R Greathouse IV, Apr 08 2015

A237276 Numbers k such that A000041(k) == 1 (mod 3).

Original entry on oeis.org

0, 1, 5, 8, 18, 19, 23, 27, 28, 34, 36, 37, 44, 45, 50, 54, 55, 59, 62, 64, 72, 73, 77, 81, 82, 86, 89, 91, 95, 98, 99, 100, 110, 112, 113, 116, 117, 118, 119, 122, 128, 134, 137, 139, 140, 143, 146, 148, 149, 150, 152, 154, 155, 157, 158, 161, 166, 168, 170
Offset: 1

Views

Author

Clark Kimberling, Feb 05 2014

Keywords

Comments

The set of positive integers is partitioned by A083214, A237276, and A237277.

Examples

			A000041(8) = 22 == 1 (mod 3).
		

Crossrefs

Programs

  • Mathematica
    f[n_, k_] := Select[Range[0, 250], Mod[PartitionsP[#], n] == k &]
    Table[f[3, k], {k, 0, 2}] (* A083214, A237276, A237277 *)
    Table[f[4, k], {k, 0, 3}] (* A237278-A237281 *)

Extensions

a(1)=0 inserted by Amiram Eldar, May 22 2025

A237280 Numbers k such that A000041(k) == 2 (mod 4).

Original entry on oeis.org

2, 8, 9, 10, 19, 22, 25, 27, 28, 31, 34, 40, 42, 45, 46, 47, 50, 57, 64, 65, 79, 86, 97, 101, 103, 110, 129, 147, 151, 158, 160, 163, 167, 170, 174, 175, 176, 184, 197, 198, 207, 213, 217, 224, 227, 228, 241, 245, 246, 247
Offset: 1

Views

Author

Clark Kimberling, Feb 05 2014

Keywords

Comments

The set of positive integers is partitioned by the sequences A237278-A237281.

Examples

			A000041(8) = 22 == 2 (mod 4).
		

Crossrefs

Programs

  • Mathematica
    f[n_, k_] := Select[Range[250], Mod[PartitionsP[#], n] == k &]
    Table[f[4, k], {k, 0, 3}] (* A237278-A237281 *)

A121062 Partition numbers mod 4.

Original entry on oeis.org

1, 1, 2, 3, 1, 3, 3, 3, 2, 2, 2, 0, 1, 1, 3, 0, 3, 1, 1, 2, 3, 0, 2, 3, 3, 2, 0, 2, 2, 1, 0, 2, 1, 3, 2, 3, 1, 1, 3, 1, 2, 3, 2, 1, 3, 2, 2, 2, 1, 1, 2, 3, 1, 3, 3, 0, 3, 2, 0, 0, 3, 1, 0, 3, 2, 2, 0, 1, 3, 1, 0, 1, 3, 1, 0, 0, 3, 3, 0, 2, 0, 3, 3, 1, 0, 1, 2, 1, 1, 1, 1, 3, 3, 1, 0, 3, 0, 2, 0, 3, 0, 2, 3, 2, 1
Offset: 0

Views

Author

Jonathan Vos Post, Aug 10 2006

Keywords

Comments

P_n==0: 11, 15, 21, 26, 30, 55, 58, 59, 62, 66, 70, 74, 75, 78, 80, 84, 94, 96, 98, 100, ... A237278.
P_n==1: 0, 1, 4, 12, 13, 17, 18, 29, 32, 36, 37, 39, 43, 48, 49, 52, 61, 67, 69, 71, 73, ... A237279.
P_n==2: 2, 8, 9, 10, 19, 22, 25, 27, 28, 31, 34, 40, 42, 45, 46, 47, 50, 57, 64, 65, 79, ... A237280.
P_n==3: 3, 5, 6, 7, 14, 16, 20, 23, 24, 33, 35, 38, 41, 44, 51, 53, 54, 56, 60, 63, 68, ... A237281.

Crossrefs

Programs

  • Maple
    b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
         (b(n, i-1)+b(n-i, min(n-i, i))) mod 4))
        end:
    a:= n-> b(n$2):
    seq(a(n), n=0..104);  # Alois P. Heinz, Dec 20 2024
  • Mathematica
    f[n_] := Mod[PartitionsP@n, 4]; Table[f@n, {n, 0, 104}] (* Robert G. Wilson v *)
  • PARI
    a(n) = numbpart(n) % 4; \\ Michel Marcus, Jun 29 2016

Formula

a(n) = A000041(n) mod 4 = A010873(A000041(n)).
a(n) = A000025(n) mod 4. - John M. Campbell, Jun 29 2016

Extensions

More terms from Robert G. Wilson v, Aug 17 2006

A237279 Numbers k such that A000041(k) == 1 (mod 4).

Original entry on oeis.org

1, 4, 12, 13, 17, 18, 29, 32, 36, 37, 39, 43, 48, 49, 52, 61, 67, 69, 71, 73, 83, 85, 87, 88, 89, 90, 93, 104, 105, 107, 114, 119, 123, 132, 143, 144, 145, 148, 150, 152, 155, 157, 162, 172, 181, 185, 186, 189, 190, 193, 194, 195, 199, 203, 208, 216, 219
Offset: 1

Views

Author

Clark Kimberling, Feb 05 2014

Keywords

Comments

The set of positive integers is partitioned by the sequences A237278-A237281.

Examples

			A000041(4) = 5 == 1 (mod 4).
		

Crossrefs

Programs

  • Mathematica
    f[n_, k_] := Select[Range[250], Mod[PartitionsP[#], n] == k &]
    Table[f[4, k], {k, 0, 3}] (* A237278-A237281 *)

A237277 Numbers k such that A000041(k) == 2 (mod 3).

Original entry on oeis.org

2, 4, 6, 11, 12, 13, 15, 25, 29, 31, 38, 42, 47, 49, 56, 58, 60, 65, 66, 67, 69, 74, 76, 78, 79, 83, 84, 85, 87, 90, 92, 93, 94, 96, 101, 103, 105, 108, 109, 114, 120, 121, 123, 126, 127, 130, 131, 132, 135, 136, 141, 144, 145, 153, 156, 159, 165, 167, 171
Offset: 1

Views

Author

Clark Kimberling, Feb 05 2014

Keywords

Comments

The set of positive integers is partitioned by A083214, A237276, and A237277.

Examples

			A000041(6) = 11 == 2 (mod 3).
		

Crossrefs

Programs

  • Mathematica
    f[n_, k_] := Select[Range[250], Mod[PartitionsP[#], n] == k &]
    Table[f[3, k], {k, 0, 2}] (* A083214, A237276, A237277 *)
    Table[f[4, k], {k, 0, 3}] (* A237278-A237281 *)
Showing 1-6 of 6 results.