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%I #8 Dec 01 2019 07:15:57
%S 1,1,2,5,1,4,1,4,1,4,1,5,2,7,2,9,3,1,4,1,6,2,9,3,1,4,1,6,2,1,3,1,5,2,
%T 8,3,1,4,1,6,2,1,3,1,5,2,8,3,1,5,1,7,2,1,4,1,6,2,1,4,1,6,2,9,3,1,5,2,
%U 8,3,1,5,2,7,3,1,4,1,7,2,1,4,1,6,2,1
%N Initial digit of Catalan number A000108(n).
%H Amiram Eldar, <a href="/A153726/b153726.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n)=A000030(A000108(n)).
%t First[IntegerDigits[#]]&/@CatalanNumber[Range[0,120]] (* _Harvey P. Dale_, Jan 20 2014 *)
%Y Cf. A000030, A008963, A077648, A152669.
%K base,nonn
%O 0,3
%A _Omar E. Pol_, Dec 30 2008
%E More terms from _Harvey P. Dale_, Jan 20 2014