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 1-3 of 3 results.

A307491 Numbers that are both centered triangular and tetrahedral.

Original entry on oeis.org

1, 4, 10, 4960, 428536
Offset: 1

Views

Author

Ilya Gutkovskiy, Apr 10 2019

Keywords

Comments

If it exists, a(6) > 10^29. - Bert Dobbelaere, Apr 12 2019

Links

Crossrefs

Intersection of A000292 and A005448.
Cf. A003556, A027568, A128862, A131750, A307492.

A307492 Numbers that are both centered square and square pyramidal.

Original entry on oeis.org

1, 5, 42925, 1026745
Offset: 1

Views

Author

Ilya Gutkovskiy, Apr 10 2019

Keywords

Comments

If it exists, a(5) > 10^29. - Bert Dobbelaere, Apr 12 2019

Links

Crossrefs

Intersection of A000330 and A001844.
Cf. A008844, A039596, A131750, A307491.

Programs

  • Mathematica
    csQ[n_] := IntegerQ[Sqrt[2*n-1]]; Select[Table[n(n+1)(2n+1)/6, {n, 0, 1000}], csQ] (* Amiram Eldar, Apr 11 2019 *)

A307493 Primes that are both centered triangular and centered square.

Original entry on oeis.org

16381, 23199907725541, 873105326726527441, 169377932722437899461, 532026300937919058017204151243671297356368598920355705257429996547710782877327451810988538831181
Offset: 1

Views

Author

Ilya Gutkovskiy, Apr 10 2019

Keywords

Comments

Primes that are the sum of three consecutive triangular numbers and the sum of two consecutive squares.
The next term is too large to include.

Links

Crossrefs

Intersection of A027862 and A125602.
Cf. A000040, A001110, A001844, A005448, A131750, A163251, A269414.

Programs

  • Mathematica
    Select[LinearRecurrence[{195, -195, 1}, {1, 85, 16381}, 43], PrimeQ[#] &]
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.