A153726 - OEIS

%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