A126299 Factorial codes for the fixed points of the square of Vaillé's 1997 bijection on Dyck paths.

0, 1, 11, 21, 111, 321, 1111, 4321, 11111, 23211, 54321, 111111, 122211, 324321, 654321, 1111111, 1222121, 2432211, 3244321, 7654321, 11111111, 22121321, 34443211, 87654321, 111111111, 122322121, 325543321, 987654321, 1111111111

Offset: 0

Author

Antti Karttunen, Jan 02 2007

Keywords

• nonn
• base

Comments

From n=31 the terms cannot anymore be presented unambiguously with decimal numbers, as A126298(31)=23713, A071156(23713)=39916799 and A007623(39916799) would result the factorial expansion "T987654321", where T stands for digit "ten".

Links

• J. Vaillé, Une Bijection Explicative de Plusieurs Propriétés Remarquables des Ponts, European J. Combin. 18 (1997), no. 1, 117-124.

Crossrefs

Cf. A071158, A126298.

Superset of A126301. Number of terms of length n is given by A126295(n).

Formula

a(n) = A071158(A126298(n)).