cp's OEIS Frontend

A302156 a(n) = Product_{k=1..n} prime(k+1)^(n-k+1).

%I A302156 #12 Apr 03 2018 15:11:32
%S A302156 1,3,45,4725,5457375,81942485625,20916229168209375,
%T A302156 101440469450294396296875,11315322731906749607393607890625,
%U A302156 36603333436941101463129791457625571484375,3670591247252362378693685549273035871463800818359375,13619248222892703567716797493618519282116254094632750020888671875
%N A302156 a(n) = Product_{k=1..n} prime(k+1)^(n-k+1).
%C A302156 a(n) is the smallest odd number with n distinct exponents in its prime factorization.
%F A302156 a(0) = 1; a(n) = A002110(n+1)*a(n-1)/2.
%F A302156 a(n) = A006939(n+1)/A000079(n+1).
%e A302156 +---+-------------------------------+
%e A302156 | n |  prime factorization of a(n)  |
%e A302156 +---+-------------------------------+
%e A302156 | 1 | 3                             |
%e A302156 | 2 | 3^2*5                         |
%e A302156 | 3 | 3^3*5^2*7                     |
%e A302156 | 4 | 3^4*5^3*7^2*11                |
%e A302156 | 5 | 3^5*5^4*7^3*11^2*13           |
%e A302156 | 6 | 3^6*5^5*7^4*11^3*13^2*17      |
%e A302156 | 7 | 3^7*5^6*7^5*11^4*13^3*17^2*19 |
%e A302156 +---+-------------------------------+
%t A302156 Table[Product[Prime[k + 1]^(n - k + 1), {k, 1, n}], {n, 0, 11}]
%o A302156 (PARI) a(n) = prod(k=1, n, prime(k+1)^(n-k+1)); \\ _Altug Alkan_, Apr 02 2018
%Y A302156 Cf. A000079, A002110, A006939, A070826, A076954, A087315.
%K A302156 nonn,easy
%O A302156 0,2
%A A302156 _Ilya Gutkovskiy_, Apr 02 2018