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%I #18 Mar 25 2021 10:22:40
%S 0,2,3,3,3,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
%T 5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%U 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6
%N a(n) is the minimal i such that A000108(i) > n.
%C Apart from the initial term 0, each n occurs A000245(n-1) times.
%o (Python)
%o from sympy import catalan
%o def a(n):
%o if n==0: return 0
%o i=1
%o while True:
%o if catalan(i)>n: return i
%o else: i+=1
%o print([a(n) for n in range(101)]) # _Indranil Ghosh_, Jun 08 2017
%o (PARI) A081288(n) = my(i=0); while(binomial(2*i, i)/(i+1) <= n, i++); i; \\ _Michel Marcus_, Apr 28 2020
%Y Cf. A000108, A000245, A072643, A081289, A081290. Used to compute A081291.
%K nonn
%O 0,2
%A _Antti Karttunen_, Mar 17 2003
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