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.

A289615 A246604 (Catalan(n)-n) with initial terms 1,0,0,2 changed to 1,1,1,3.

Original entry on oeis.org

1, 1, 1, 3, 10, 37, 126, 422, 1422, 4853, 16786, 58775, 208000, 742887, 2674426, 9694830, 35357654, 129644773, 477638682, 1767263171, 6564120400, 24466266999, 91482563618, 343059613627, 1289904147300, 4861946401427, 18367353072126, 69533550915977, 263747951750332, 1002242216651339
Offset: 1

Views

Author

N. J. A. Sloane, Jul 09 2017

Keywords

Comments

Related to number of mesh patterns of length 2 that avoid the pattern 321.

Crossrefs

A variant of A246604.
All of A000108, A001453, A246604, A273526, A120304, A289615, A289616, A289652, A289653, A289654 are very similar sequences.

Programs

  • Mathematica
    Join[{1,1,1,3},Array[CatalanNumber[#]-#&,30,4]] (* Paolo Xausa, Dec 08 2023 *)