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A243054 a(0)=1, and for n >= 1, a(n) = p_n * A002110(n) / 2, where p_n is the n-th prime.

%I A243054 #13 Apr 28 2021 02:41:33
%S A243054 1,2,9,75,735,12705,195195,4339335,92147055,2565568005,93810551835,
%T A243054 3108687597015,137283655493985,6237130402307805,281279368630905645,
%U A243054 14449909890829548135,863612699645536185345,56721430329549272852565,3577295631461912614989735,263253771961188946371949515
%N A243054 a(0)=1, and for n >= 1, a(n) = p_n * A002110(n) / 2, where p_n is the n-th prime.
%C A243054 Fixed points of A243051.
%C A243054 From n >= 2 onward: a(n) = the product of the first n-1 odd primes multiplied by the n-th prime.
%F A243054 a(0)=1, and for n >= 1, a(n) = A000040(n)*A002110(n)/2.
%F A243054 a(0)=1, a(1)=2 and for n >= 2, a(n) = A006530(A070826(n)) * A070826(n).
%o A243054 (Scheme) (define (A243054 n) (if (zero? n) 1 (* (/ 1 2) (A000040 n) (A002110 n))))
%Y A243054 Cf. A000040, A002110, A006530, A070826, A243051.
%K A243054 nonn,easy
%O A243054 0,2
%A A243054 _Antti Karttunen_, May 29 2014