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%I #8 Feb 18 2021 05:41:41
%S 3,4,6,8,10,12,14,16,19,21,23,25,28,30,32,34,37,39,41,43,46,48,50,52,
%T 55,57,59,62,64,66,68,71,73,75,78,80,82,84,87,89,91,94,96,98,101,103,
%U 105,108,110,112,114,117,119,121,124,126,128,131,133,135,138
%N Least k such that k!! > prime(1)*prime(2)*...*prime(n) where prime(n) is the n-th prime.
%o (PARI) dbf(n) = prod(i = 0, floor((n-1)/2), n - 2*i );
%o a(n) = pr = prod(i = 1, n, prime(i)); k = 1; while(dbf(k) <= pr, k++); k; \\ _Michel Marcus_, Oct 13 2013
%Y Cf. A002110, A006882, A073071.
%K nonn
%O 1,1
%A _Zak Seidov_, May 01 2008
%E More terms from _Michel Marcus_, Oct 13 2013