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%I #7 Dec 08 2022 20:46:18
%S 1,1,2,36,48708493958471199415506599153950129703565945470976
%N Factorials successively exponentiated.
%C a(5) > 10^(10^50).
%F a(n) = n!^a(n - 1) starting with a(0)=0!=1.
%e a(3) = 36 because 3!^(2!^(1!^0!)) = 36
%t a[0] := 1 a[n_Integer] := n!^a[n - 1]
%Y Cf. A049384, A358972 (exponents left to right).
%K easy,nonn
%O 0,3
%A Jon Kongsvold (Jon.Kongsvold(AT)idi.ntnu.no), Aug 28 2002
%E Edited by _Henry Bottomley_, Jul 13 2003