1,5

Table of n, a(n) for n=1..20.

Column k=2 (or k=-2) of A062866.

Equal number moved left and right, see A062868.

Sequence in context: A263784 A263785 A263786 * A162443 A219678 A297743

Adjacent sequences: A169931 A169932 A169933 * A169935 A169936 A169937

nonn

R. H. Hardin, Jul 19 2010

a(19)-a(20) from Alois P. Heinz, Jul 31 2018

approved