1,2

Table of n, a(n) for n=1..7.

The following triangle of 4 rows satisfies the requirements:

....1

...3 2

..4 5 8

.6 7 9 10

a(n)=6*A064050(n) for n>1.

Sequence in context: A200904 A293488 A038033 * A336267 A018981 A052594

Adjacent sequences: A064046 A064047 A064048 * A064050 A064051 A064052

more,nonn

Floor van Lamoen, Aug 24 2001

a(7) from Lars Blomberg, Apr 11 2012

approved