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%I #17 Oct 02 2022 00:23:54
%S 7,153,197,7399,24434,24434,9242360,238861211,238861211
%N a(n) is the smallest k such that k! has at least n consecutive zeros immediately after the leading digit in base 10.
%e a(1) = 7, because 7! = 5040 has one zero immediately after the leading digit, and there is no k<7 with that property.
%o (Python)
%o from itertools import count
%o t = 1
%o n = 1
%o for k in count(1):
%o t *= k
%o while str(t)[1:1+n] == '0'*n:
%o print(n,k)
%o n += 1
%Y Cf. A000142, A027869.
%K nonn,base,more
%O 1,1
%A _Christian Perfect_, Aug 25 2022
%E a(5)-a(6) from _Amiram Eldar_, Aug 25 2022
%E a(7)-a(9) from _Jinyuan Wang_, Aug 25 2022
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