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%I #15 Jun 22 2022 14:44:54
%S 1,2,5,1,2,1,1,10,1,1,2,1,1,2,5,1,6,7,1,4,3,3,2,3,37,34,47,5,68,53,11,
%T 2,1,39,14,1,1,2,1,1,4,1,77745,4,5,5,126,51,1,6,1,1,44,1,1,12,31,1,2,
%U 3,663,46,51,5,2,41,1,4,3,5,29318,445,3,6,1,39,4,5,31,4,5,23,2,1
%N a(n) = gcd(A000108(n), A000110(n)).
%H Amiram Eldar, <a href="/A091772/b091772.txt">Table of n, a(n) for n = 1..10000</a>
%t Table[GCD[CatalanNumber[n], BellB[n]], {n, 1, 84}] (* _Amiram Eldar_, Nov 23 2019 *)
%o (Python)
%o from itertools import count, accumulate, islice
%o def A091772_gen(): # generator of terms
%o yield 1
%o blist, b, c = (1,2), 1, 1
%o for n in count(1):
%o blist = list(accumulate(blist, initial=(b:=blist[-1])))
%o yield gcd(b, c := c*(4*n+2)//(n+2))
%o A091772_list = list(islice(A091772_gen(),20)) # _Chai Wah Wu_, Jun 22 2022
%Y Cf. A000108 (Catalan numbers), A000110 (Bell Numbers).
%K nonn
%O 1,2
%A _Jon Perry_, Mar 06 2004
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