cp's OEIS Frontend

A228593 Products of 2 successive primorials.

%I A228593 #30 Aug 14 2025 19:41:52
%S A228593 2,12,180,6300,485100,69369300,15330615300,4951788741900,
%T A228593 2163931680210300,1443342430700270100,1297564845199542819900,
%U A228593 1488306877443875614425300,2257761533082359307083180100,3980433582824199458387646516300,8044456270887707105401433609442300
%N A228593 Products of 2 successive primorials.
%C A228593 No sum of any number of terms is a perfect power.
%H A228593 Michael De Vlieger, <a href="/A228593/b228593.txt">Table of n, a(n) for n = 1..196</a>
%H A228593 Wikipedia, <a href="http://en.wikipedia.org/wiki/Perfect_power">Perfect power</a>.
%F A228593 a(1) = 2; a(n) = 2*(Product_{i=1..n-1} A006094(i)), n >= 2.
%F A228593 a(n) = A002110(n-1)*A002110(n); n >= 1. - _David James Sycamore_, Jul 13 2023
%F A228593 a(1) = 2, for n>1 a(n) = a(n-1)*prime(n-1)*prime(n). - _David James Sycamore_, Jul 15 2023
%t A228593 nxt[{n_,a_}]:={n+1,a Prime[n]Prime[n+1]}; NestList[nxt,{1,2},20][[All,2]] (* _Harvey P. Dale_, Feb 19 2020 *)
%o A228593 (Magma) [n le 1 select 2 else Self(n-1)*NthPrime(n-1)*NthPrime(n): n in [1..14]];
%o A228593 (PARI) a(n) = vecprod(primes(n-1))*vecprod(primes(n)); \\ _Michel Marcus_, Aug 11 2023
%Y A228593 Cf. A000040, A001597, A006094, A002110.
%K A228593 easy,nonn
%O A228593 1,1
%A A228593 _Arkadiusz Wesolowski_, Aug 27 2013