A169952 Second entry in row n of triangle in A169950.

1, 2, 5, 8, 13, 20, 33, 48, 75, 100, 145, 204, 293, 396, 559, 746, 1027, 1340, 1809, 2342, 3177, 4050, 5369, 6920, 9013, 11360, 14837, 18718, 24081, 29952, 38219, 47662, 60549, 74618, 93847, 115960, 145319, 177548, 221675, 270334, 335123, 406290, 500915

Offset: 1

Author

N. J. A. Sloane, Aug 01 2010

Keywords

• nonn

Comments

Wanted: a recurrence. Are any of A169940-A169954 related to any other entries in the OEIS?

Links

• Fausto A. C. Cariboni, Table of n, a(n) for n = 1..99 (terms 1..64 from Andrew Howroyd)
• Index entries for sequences related to carryless arithmetic

Crossrefs

Related to thickness: A169940-A169954, A061909.

Programs

Mathematica

A169947 = Import["https://oeis.org/A169947/b169947.txt", "Table"][[All, 2]];
Join[{1}, Differences[A169947]] (* Jean-François Alcover, Sep 02 2019 *)

Formula

a(n) = A169947(n) - A169947(n-1) for n>1. - Andrew Howroyd, Jul 09 2017

Extensions

a(16)-a(29) from Nathaniel Johnston, Nov 15 2010

Terms a(30) and beyond from Andrew Howroyd, Jul 09 2017