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 A131809 Multiplicative persistence of Catalan numbers. 1
 0, 0, 0, 0, 1, 1, 1, 3, 1, 5, 4, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 COMMENTS After the 57th terms all the numbers have some digits equal to zero thus the persistence is equal to 1. LINKS EXAMPLE Catalan number 429 -> 4*2*9=72 -> 7*2=14 -> 1*4=4 thus persistence is 3 MAPLE P:=proc(n) local i, k, w, ok, cont; for i from 0 by 1 to n do k:=(2*i)!/(i!*(i+1)!); w:=1; ok:=1; if k<10 then print(0); else cont:=1; while ok=1 do while k>0 do w:=w*(k-(trunc(k/10)*10)); k:=trunc(k/10); od; if w<10 then ok:=0; print(cont); else cont:=cont+1; k:=w; w:=1; fi; od; fi; od; end: P(100); CROSSREFS Cf. A003001, A006050, A000108. Sequence in context: A308502 A308674 A308676 * A016574 A210560 A208922 Adjacent sequences:  A131806 A131807 A131808 * A131810 A131811 A131812 KEYWORD easy,nonn,base AUTHOR Paolo P. Lava and Giorgio Balzarotti, Jul 18 2007 STATUS approved

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Last modified December 1 07:59 EST 2021. Contains 349426 sequences. (Running on oeis4.)