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 1-10 of 11 results. Next

A051343 Number of ways of writing n as a sum of 3 nonnegative cubes (counted naively).

Original entry on oeis.org

1, 3, 3, 1, 0, 0, 0, 0, 3, 6, 3, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 1, 0, 0, 3, 6, 3, 0, 0, 0, 0, 0, 6, 6, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 3, 0, 0, 0, 0, 0, 0, 3, 0, 3, 6, 3, 0, 0, 0, 0, 0, 6, 6, 0, 0, 0, 0, 0, 0, 3, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 6
Offset: 0

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Author

Keywords

Crossrefs

Cf. A051344.
Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

Programs

  • Maple
    series(add(x^(n^3), n=0..10)^3,x,1000);
  • PARI
    first(n)=my(s=vector(n+1)); for(k=0,sqrtnint(n,3), s[k^3+1]=1); Vec(Ser(s,,n+1)^3) \\ Charles R Greathouse IV, Sep 16 2016

A173677 Number of ways of writing n as a sum of two nonnegative cubes.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Nov 24 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^2.

Crossrefs

Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

Programs

Formula

a(n) = Sum_{k=0..n} c(k) * c(n-k), where c = A010057. - Wesley Ivan Hurt, Nov 09 2023

A173682 Number of ways of writing n as a sum of 9 nonnegative cubes.

Original entry on oeis.org

1, 9, 36, 84, 126, 126, 84, 36, 18, 73, 252, 504, 630, 504, 252, 72, 45, 252, 756, 1260, 1260, 756, 252, 36, 84, 504, 1260, 1689, 1332, 756, 588, 630, 630, 882, 1332, 1341, 1134, 1638, 2520, 2520, 1638, 1008, 828, 756, 1638, 3780, 5040, 3780, 1596, 504, 252, 588, 2520, 5040, 5076, 2772, 1296, 1332, 1296, 1386, 2772, 3816, 2772, 2142, 3798, 5121, 4032
Offset: 0

Views

Author

N. J. A. Sloane, Nov 25 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^9.

Crossrefs

Cf. A173677.
Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

A173676 Number of ways of writing n as a sum of seven nonnegative cubes.

Original entry on oeis.org

1, 7, 21, 35, 35, 21, 7, 1, 7, 42, 105, 140, 105, 42, 7, 0, 21, 105, 210, 210, 105, 21, 0, 0, 35, 140, 210, 147, 77, 105, 140, 105, 77, 112, 105, 77, 210, 420, 420, 210, 63, 42, 21, 105, 420, 630, 420, 105, 7, 7, 0, 140, 420, 420, 161, 105, 211, 210, 105, 126, 210, 105, 105, 420, 637, 462, 210, 182, 147, 42, 217, 630, 672, 420, 420, 427, 210, 42
Offset: 0

Views

Author

N. J. A. Sloane, Nov 24 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^7.
It is known that a(n)>0 if n is even and > 454.

Crossrefs

Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

A173678 Number of ways of writing n as a sum of 4 nonnegative cubes.

Original entry on oeis.org

1, 4, 6, 4, 1, 0, 0, 0, 4, 12, 12, 4, 0, 0, 0, 0, 6, 12, 6, 0, 0, 0, 0, 0, 4, 4, 0, 4, 12, 12, 4, 0, 1, 0, 0, 12, 24, 12, 0, 0, 0, 0, 0, 12, 12, 0, 0, 0, 0, 0, 0, 4, 0, 0, 6, 12, 6, 0, 0, 0, 0, 0, 12, 12, 4, 12, 12, 4, 0, 0, 6, 0, 12, 24, 12, 0, 0, 0, 0, 0, 12, 16, 4, 0, 0, 0, 0, 0, 4, 4, 0, 12, 24, 12, 0, 0, 0, 0, 0, 24, 24, 0, 0, 0, 0, 0, 0, 12, 1, 0, 0
Offset: 0

Views

Author

N. J. A. Sloane, Nov 24 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^4.

Crossrefs

Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.
Without order you get A025448.

A173679 Number of ways of writing n as a sum of 5 nonnegative cubes.

Original entry on oeis.org

1, 5, 10, 10, 5, 1, 0, 0, 5, 20, 30, 20, 5, 0, 0, 0, 10, 30, 30, 10, 0, 0, 0, 0, 10, 20, 10, 5, 20, 30, 20, 5, 5, 5, 0, 20, 60, 60, 20, 0, 1, 0, 0, 30, 60, 30, 0, 0, 0, 0, 0, 20, 20, 0, 10, 30, 30, 10, 0, 5, 0, 0, 30, 60, 35, 20, 30, 20, 5, 0, 30, 30, 20, 60, 60, 20, 0, 0, 10, 0, 30, 70, 50, 10, 0, 0, 0, 0, 20, 40, 20, 20, 60, 60, 20, 0, 5, 10, 0, 60, 120
Offset: 0

Views

Author

N. J. A. Sloane, Nov 25 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^5.

Crossrefs

Cf. A173677.
Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

A173681 Number of ways of writing n as a sum of 8 nonnegative cubes.

Original entry on oeis.org

1, 8, 28, 56, 70, 56, 28, 8, 9, 56, 168, 280, 280, 168, 56, 8, 28, 168, 420, 560, 420, 168, 28, 0, 56, 280, 560, 568, 336, 224, 280, 280, 238, 336, 428, 336, 406, 840, 1120, 840, 392, 224, 168, 224, 840, 1680, 1680, 840, 196, 56, 28, 280, 1120, 1680, 1148, 448, 428, 568, 420, 448, 868, 840, 448, 840, 1689, 1736, 1008, 616, 616, 336, 476, 1688, 2576
Offset: 0

Views

Author

N. J. A. Sloane, Nov 25 2010

Keywords

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^8.

Crossrefs

Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

Programs

  • PARI
    lista(n)=my(q='q); Vec(sum(m=0, (n+.5)^(1/3), q^(m^3), O(q^(n+1)))^8); \\ Michel Marcus, Apr 12 2016

A340979 Number of ways to write n as an ordered sum of 6 positive cubes.

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 0, 6, 0, 0, 0, 0, 0, 0, 15, 0, 0, 0, 0, 0, 0, 20, 0, 0, 0, 0, 6, 0, 15, 0, 0, 0, 0, 30, 0, 6, 0, 0, 0, 0, 60, 0, 1, 0, 0, 0, 0, 60, 0, 0, 0, 0, 15, 0, 30, 0, 0, 0, 0, 60, 0, 6, 0, 6, 0, 0, 90, 0, 0, 0, 30, 0, 0, 60, 0, 0, 0, 60, 20, 0, 15, 0, 0, 0, 60, 60, 0, 0, 0, 30, 0, 30, 60
Offset: 6

Views

Author

Ilya Gutkovskiy, Feb 01 2021

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, t) option remember;
          `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add((s->
          `if`(s>n, 0, b(n-s, t-1)))(j^3), j=1..iroot(n, 3))))
        end:
    a:= n-> b(n, 6):
    seq(a(n), n=6..98);  # Alois P. Heinz, Feb 01 2021
  • Mathematica
    nmax = 98; CoefficientList[Series[Sum[x^(k^3), {k, 1, Floor[nmax^(1/3)] + 1}]^6, {x, 0, nmax}], x] // Drop[#, 6] &

Formula

G.f.: (Sum_{k>=1} x^(k^3))^6.

A290054 Square array A(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of (Sum_{j>=0} x^(j^3))^k.

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 2, 0, 0, 1, 3, 1, 0, 0, 1, 4, 3, 0, 0, 0, 1, 5, 6, 1, 0, 0, 0, 1, 6, 10, 4, 0, 0, 0, 0, 1, 7, 15, 10, 1, 0, 0, 0, 0, 1, 8, 21, 20, 5, 0, 0, 0, 1, 0, 1, 9, 28, 35, 15, 1, 0, 0, 2, 0, 0, 1, 10, 36, 56, 35, 6, 0, 0, 3, 2, 0, 0, 1, 11, 45, 84, 70, 21, 1, 0, 4, 6, 0, 0, 0
Offset: 0

Views

Author

Ilya Gutkovskiy, Jul 19 2017

Keywords

Comments

A(n,k) is the number of ways of writing n as a sum of k nonnegative cubes.

Examples

			Square array begins:
1,  1,  1,  1,  1,   1,  ...
0,  1,  2,  3,  4,   5,  ...
0,  0,  1,  3,  6,  10,  ...
0,  0,  0,  1,  4,  10,  ...
0,  0,  0,  0,  1,   5,  ...
0,  0,  0,  0,  0,   1,  ...
		

Crossrefs

Main diagonal gives A291700.
Antidiagonal sums give A302019.

Programs

  • Mathematica
    Table[Function[k, SeriesCoefficient[Sum[x^i^3, {i, 0, n}]^k, {x, 0, n}]][j - n], {j, 0, 12}, {n, 0, j}] // Flatten

Formula

G.f. of column k: (Sum_{j>=0} x^(j^3))^k.

A004829 Numbers that are the sum of at most 7 positive cubes.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69
Offset: 1

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Author

Keywords

Comments

McCurley proves that every n > exp(exp(13.97)) is in A003330 and hence in this sequence. Siksek proves that all n > 454 are in this sequence. - Charles R Greathouse IV, Jun 29 2022

Crossrefs

Complement of A018889; subsequence of A003330.
Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.
Cf. A018888.
Showing 1-10 of 11 results. Next