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 1-4 of 4 results.

A365167 Number of representations of n as the sum of a prime number and a fourth power of a positive integer.

Original entry on oeis.org

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

Views

Author

Ilya Gutkovskiy, Aug 24 2023

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 120; CoefficientList[Series[Sum[x^Prime[i], {i, 1, nmax}] Sum[x^j^4, {j, 1, nmax^(1/4)}], {x, 0, nmax}], x] // Rest

Formula

G.f.: (Sum_{i>=1} x^prime(i)) * (Sum_{j>=1} x^(j^4)).

A365291 a(n) is the least positive integer that can be expressed as the sum of a prime number and a fourth power of a nonnegative integer in exactly n ways.

Original entry on oeis.org

1, 2, 3, 83, 1298, 4259, 11087, 22637, 65579, 102044, 181838, 234527, 467627, 754652, 991889, 1431113, 1875902, 2271407, 4102958, 4851593, 8458148, 6826874, 10715858, 15453983, 18805058, 23502134, 27671573, 34425893, 34967159, 47158793, 54659384, 78188129, 67269347
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 31 2023

Keywords

Examples

			For n = 3: 83 = 2 + 3^4 = 67 + 2^4 = 83 + 0^4.
		

Crossrefs

Extensions

More terms from Jinyuan Wang, Sep 13 2023

A365127 Numbers that are the sum of a prime number and a fourth power of a nonnegative integer.

Original entry on oeis.org

2, 3, 4, 5, 6, 7, 8, 11, 12, 13, 14, 17, 18, 19, 20, 21, 23, 24, 27, 29, 30, 31, 32, 33, 35, 37, 38, 39, 41, 42, 43, 44, 45, 47, 48, 53, 54, 57, 59, 60, 61, 62, 63, 67, 68, 69, 71, 72, 73, 74, 75, 77, 79, 80, 83, 84, 86, 87, 88, 89, 90, 92, 94, 95, 97, 98, 99, 100
Offset: 1

Views

Author

Ilya Gutkovskiy, Aug 24 2023

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 100; f[x_] := Sum[x^Prime[i], {i, 1, nmax}] Sum[x^j^4, {j, 0, nmax^(1/4)}]; Exponent[#, x] & /@ List @@ Normal[Series[f[x], {x, 0, nmax}]]

A365166 Numbers that are not the sum of a prime number and a fourth power of a nonnegative integer.

Original entry on oeis.org

1, 9, 10, 15, 16, 22, 25, 26, 28, 34, 36, 40, 46, 49, 50, 51, 52, 55, 56, 58, 64, 65, 66, 70, 76, 78, 81, 82, 85, 91, 93, 96, 106, 111, 115, 116, 120, 121, 126, 130, 133, 135, 136, 141, 144, 145, 146, 156, 159, 161, 162, 166, 169, 171, 172, 175, 176, 177, 185, 186, 187, 196
Offset: 1

Views

Author

Ilya Gutkovskiy, Aug 24 2023

Keywords

Crossrefs

Programs

  • Mathematica
    nmax = 197; Position[CoefficientList[Series[Sum[x^Prime[i], {i, 1, nmax}] Sum[x^j^4, {j, 0, nmax^(1/4)}], {x, 0, nmax}], x] // Rest, 0] // Flatten
Showing 1-4 of 4 results.