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%I #11 Sep 24 2020 11:37:54
%S 0,4,27,81,3125,15625,823543,5764801,40353607,282475249,285311670611,
%T 3138428376721,302875106592253,3937376385699289,51185893014090757,
%U 665416609183179841,827240261886336764177,14063084452067724991009
%N Largest number with n prime factors where all factors are less than or equal to n.
%F a(n) = A007917(n)^n for n>1. - _Michel Marcus_, Sep 24 2020
%e a(2) = 4 (4=2*2 has 2 factors and 2 is the largest prime number <= 2).
%e a(3) = 27 (27=3*3*3 has 3 factors and 3 is the largest prime number <= 3).
%e a(4) = 81 (81=3*3*3*3 has 4 factors and 3 is the largest prime number <= 4).
%t a[n_] := If[n == 1, 0, If[PrimeQ[n], n, NextPrime[n, -1]]^n];
%t Array[a, 18] (* _Jean-François Alcover_, Sep 24 2020 *)
%o (PARI) a(n) = if (n==1, 0, precprime(n)^n); \\ _Michel Marcus_, Sep 24 2020
%Y Cf. A007917 (largest prime <= n).
%K easy,nonn
%O 1,2
%A Jostein Trondal (jallamekk(AT)hotmail.com), May 13 2002
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