OFFSET
1,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..200
FORMULA
a(n) = A214258(2n,n).
Conjecture: a(n) ~ n * 2^(n-3). - Vaclav Kotesovec, Jan 07 2019
EXAMPLE
a(2) = 2: 13, 31.
a(3) = 3: 114, 141, 411.
a(4) = 12: 1115, 1151, 1511, 5111, 125, 152, 215, 251, 512, 521, 26, 62.
a(5) = 23: 11116, 11161, 11611, 16111, 61111, 1126, 1162, 1216, 1261, 1612, 1621, 2116, 2161, 2611, 6112, 6121, 6211, 136, 163, 316, 361, 613, 631.
CROSSREFS
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jan 04 2019
STATUS
approved