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 A131810 Additive persistence of Catalan numbers. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 LINKS 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: A182598 A331084 A067694 * A233519 A192295 A037195 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

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Last modified January 22 12:12 EST 2022. Contains 350481 sequences. (Running on oeis4.)