A131810 Additive persistence of Catalan numbers.

0, 0, 0, 0, 1, 1, 1, 2, 1, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 3, 3, 3, 3, 2, 3, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 3, 2, 2, 2, 3, 2, 4, 3, 2, 3

Offset

0,8

Links

Table of n, a(n) for n=0..87.

Example

Catalan number 429 -> 4+2+9=15 -> 1+5=6 thus persistence is 2

Maple

with(numtheory): with(combinat): P:=proc(n) local a, t; t:=0; a:=(2*n)!/(n!*(n+1)!); while a>9 do t:=t+1; a:=convert(convert(a, base, 10), `+`); od; t;
end: seq(P(i), i=0..10^2);

Crossrefs

Cf. A003001, A006050, A000108, A131809.

Sequence in context: A331084 A067694 A390877 * A365143 A233519 A192295

Adjacent sequences: A131807 A131808 A131809 * A131811 A131812 A131813

Keyword

easy,nonn,base

Author

Paolo P. Lava and Giorgio Balzarotti, Jul 18 2007

Extensions

Corrected entries and Maple code by Paolo P. Lava, Dec 19 2017

Status

approved