A269967 Indices of zeros in A269783.

0, 1, 4, 7, 15, 23, 40, 55, 85, 111, 158, 197, 265, 323, 416, 493, 615, 719, 874, 1005, 1197, 1361, 1594, 1793, 2071, 2313, 2640, 2921, 3301, 3633, 4070, 4453, 4951, 5389, 5952, 6447, 7079, 7641, 8346, 8971, 9753, 10453, 11316, 12087, 13035, 13885, 14922

Offset: 1

Author

M. F. Hasler, Mar 08 2016

Keywords

• nonn

Comments

Sequence A269783 is defined by A269783(0)=0 and A269783(n+1) = A269783(n) + (-1)^(k+e)*floor(k/2), where k = #{ j<=n | A269783(j)=A269783(n) } and e=1 for A269783(n)>0, else e=0. That is, the 1st, 2nd, 3rd, 4th... occurrence of any positive integer n is followed by n resp. n-1 resp. n+1 resp. n-2, etc., and for zero or negative integers the same with opposite sign.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..10000
• Rémy Sigrist, C++ program

Crossrefs

Cf. A269783 (main sequence), A269968 (index of first occurrence of n), A269969 (index of first occurrence of -n).

Extensions

More terms from Rémy Sigrist, May 21 2023