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 1-8 of 8 results.

A341142 Number of partitions of n into 5 distinct prime powers (including 1).

Original entry on oeis.org

1, 0, 1, 2, 3, 3, 5, 5, 7, 8, 10, 12, 15, 15, 18, 21, 23, 26, 31, 33, 36, 41, 43, 48, 52, 58, 62, 72, 72, 82, 85, 95, 97, 112, 112, 125, 127, 142, 142, 161, 159, 181, 180, 200, 196, 222, 217, 243, 239, 269, 261, 291, 284, 316, 308, 341, 332, 370, 358, 394, 381, 427, 414, 456
Offset: 15

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Links

Crossrefs

Cf. A000961, A010055, A341123, A341132, A341134, A341140, A341141, A341143, A341144, A341145.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
      `if`(q(i), b(n-i, min(n-i, i-1), t-1), 0)))
    end:
a:= n-> b(n$2, 5):
seq(a(n), n=15..78);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    q[n_] := q[n] = PrimeNu[n] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
     If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
     If[q[i], b[n - i, Min[n - i, i - 1], t - 1], 0]]];
a[n_] := b[n, n, 5];
Table[a[n], {n, 15, 78}] (* Jean-François Alcover, Jul 13 2021, after Alois P. Heinz *)
Table[Count[IntegerPartitions[n,{5}],?(Max[PrimeNu[#]]<2&&Length[#]==Length[Union[#]]&)],{n,15,80}] (* _Harvey P. Dale, Dec 22 2024 *)

A341133 Number of ways to write n as an ordered sum of 4 prime powers (including 1).

Original entry on oeis.org

1, 4, 10, 20, 35, 52, 72, 96, 125, 156, 196, 236, 277, 316, 362, 400, 451, 496, 554, 604, 668, 704, 770, 808, 871, 920, 1014, 1040, 1131, 1172, 1266, 1308, 1449, 1484, 1638, 1672, 1802, 1820, 1992, 1964, 2167, 2172, 2332, 2296, 2534, 2444, 2698, 2648, 2889, 2820, 3140
Offset: 4

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341122, A341134, A341135, A341136, A341137, A341138, A341139.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 4):
seq(a(n), n=4..54);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 54; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^4, {x, 0, nmax}], x] // Drop[#, 4] &

A341135 Number of ways to write n as an ordered sum of 6 prime powers (including 1).

Original entry on oeis.org

1, 6, 21, 56, 126, 246, 432, 702, 1077, 1576, 2232, 3072, 4118, 5382, 6891, 8638, 10653, 12948, 15563, 18486, 21783, 25398, 29394, 33708, 38422, 43452, 49008, 54888, 61308, 68076, 75434, 83034, 91473, 100248, 109947, 120018, 131191, 142458, 155049, 167622, 181629, 195660
Offset: 6

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341124, A341133, A341134, A341136, A341137, A341138, A341139.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 6):
seq(a(n), n=6..47);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 47; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^6, {x, 0, nmax}], x] // Drop[#, 6] &

A341138 Number of ways to write n as an ordered sum of 9 prime powers (including 1).

Original entry on oeis.org

1, 9, 45, 165, 495, 1278, 2931, 6111, 11790, 21331, 36594, 60057, 94938, 145296, 216153, 313524, 444483, 617229, 841225, 1127187, 1487322, 1935252, 2486124, 3156408, 3964218, 4928841, 6071472, 7414669, 8983179, 10802970, 12902661, 15311277, 18061092, 21185103, 24720552
Offset: 9

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Links

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341127, A341133, A341134, A341135, A341136, A341137, A341139.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 9):
seq(a(n), n=9..43);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 43; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^9, {x, 0, nmax}], x] // Drop[#, 9] &

A341136 Number of ways to write n as an ordered sum of 7 prime powers (including 1).

Original entry on oeis.org

1, 7, 28, 84, 210, 455, 882, 1569, 2611, 4116, 6223, 9093, 12901, 17822, 24053, 31759, 41132, 52367, 65702, 81326, 99526, 120471, 144417, 171493, 201985, 235963, 273889, 315805, 362181, 413021, 468888, 529466, 595770, 667541, 745899, 830473, 922866, 1021832, 1129499
Offset: 7

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341125, A341133, A341134, A341135, A341137, A341138, A341139.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 7):
seq(a(n), n=7..45);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 45; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^7, {x, 0, nmax}], x] // Drop[#, 7] &

A341137 Number of ways to write n as an ordered sum of 8 prime powers (including 1).

Original entry on oeis.org

1, 8, 36, 120, 330, 784, 1660, 3208, 5763, 9752, 15724, 24368, 36520, 53152, 75392, 104464, 141717, 188624, 246836, 318088, 404356, 507656, 630172, 774048, 941685, 1135304, 1357652, 1611240, 1899138, 2224016, 2589352, 2997544, 3452619, 3957480, 4516912, 5134096, 5815338
Offset: 8

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341126, A341133, A341134, A341135, A341136, A341138, A341139.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 8):
seq(a(n), n=8..44);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 44; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^8, {x, 0, nmax}], x] // Drop[#, 8] &

A341139 Number of ways to write n as an ordered sum of 10 prime powers (including 1).

Original entry on oeis.org

1, 10, 55, 220, 715, 1992, 4915, 10990, 22660, 43660, 79463, 137830, 229460, 368710, 574410, 870644, 1287545, 1862110, 2639135, 3672050, 5024035, 6768950, 8992340, 11792070, 15279450, 19579514, 24832415, 31193900, 38837085, 47952400, 58750125, 71458860, 86328885
Offset: 10

Views

Author

Ilya Gutkovskiy, Feb 05 2021

Keywords

Crossrefs

Cf. A000961, A010055, A282062, A282064, A341131, A341133, A341134, A341135, A341136, A341137, A341138.

Programs

  • Maple
    q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
      `if`(q(j), b(n-j, t-1), 0), j=1..n)))
    end:
a:= n-> b(n, 10):
seq(a(n), n=10..42);  # Alois P. Heinz, Feb 05 2021
  • Mathematica
    nmax = 42; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^10, {x, 0, nmax}], x] // Drop[#, 10] &

A347775 Number of compositions (ordered partitions) of n into at most 5 prime powers (including 1).

Original entry on oeis.org

1, 1, 2, 4, 8, 16, 30, 55, 94, 151, 227, 326, 450, 603, 786, 1005, 1259, 1543, 1856, 2201, 2571, 2978, 3417, 3896, 4402, 4950, 5506, 6104, 6710, 7366, 8040, 8792, 9526, 10342, 11150, 12042, 12918, 13977, 14975, 16145, 17242, 18514, 19628, 21015, 22170, 23671, 24940
Offset: 0

Views

Author

Ilya Gutkovskiy, Sep 13 2021

Keywords

Crossrefs

Cf. A000961, A280543, A341134, A347762, A347763, A347764, A347776.

Programs

  • Mathematica
    Table[Length@Flatten[Permutations/@IntegerPartitions[n,5,Join[{1},Select[Range@n,PrimePowerQ]]],1],{n,0,46}] (* Giorgos Kalogeropoulos, Sep 13 2021 *)
Showing 1-8 of 8 results.

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