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%I #10 Dec 13 2014 00:38:27
%S 1,2,8,51,496,6041,97155,1746481,38377034,1053921489,31722366805,
%T 1127475187757,45429396874080,1910408631449923,87682336584597009,
%U 4571067440374822934,260160909199262899454,15823372061924831882182,1034588557961336117180784,72606463908572608290939197,5235472173106695729625747152,407296805992490241506213234700
%N a(n) = floor((A002110(n) * A054272(n)) / A001248(n)).
%H Antti Karttunen, <a href="/A249747/b249747.txt">Table of n, a(n) for n = 1..100</a>
%F a(n) = floor((A002110(n) * A054272(n)) / A001248(n)).
%F The ratio a(n) / A005867(n) seems to stay near 1. Note that A005867(n) = A000010(A002110(n)). See also formulas in A054272.
%o (MIT/GNU Scheme) (define (A249747 n) (floor->exact (/ (* (A002110 n) (A054272 n)) (A001248 n))))
%o (PARI)
%o default(primelimit, 2^31 + 2^30);
%o A002110(n) = prod(i=1, n, prime(i));
%o A054272(n) = 1 + primepi(prime(n)^2) - n;
%o A249747(n) = (A054272(n)*A002110(n))\(prime(n)^2);
%o for(n=1, 100, write("b249747.txt", n, " ", A249747(n)));
%Y Cf. A000010, A001248, A002110, A005867, A054272.
%K nonn
%O 1,2
%A _Antti Karttunen_, Dec 08 2014