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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A346425 a(n) is the greatest number k such that k! <= prime(n).

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%I A346425 #29 Jul 20 2021 04:02:42
%S A346425 2,2,2,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,
%T A346425 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
%U A346425 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5
%N A346425 a(n) is the greatest number k such that k! <= prime(n).
%C A346425 Terms 2, 3, 4, 5, ... appear respectively 3, 6, 21, 98, ... times consecutively; indeed, 2 appears A061232(1) + A061232(2) times, then every m >= 3 appears A061232(m) times.
%F A346425 a(n)! = A000040(n) - A136437(n).
%e A346425 prime(1) = 2 and the greatest k with k! <= 2 is 2, so a(1) = 2.
%e A346425 prime(4) = 7 and the greatest k with k! <= 7 is 3, so a(4) = 3.
%e A346425 prime(10) = 29 and the greatest k with k! <= 29 is 4 so a(10) = 4.
%e A346425 Rows with n, prime(n), greatest k! <=n, a(n) for n = 1..14
%e A346425       n        1    2    3    4    5    6    7    8    9   10   11   12   13   14
%e A346425    prime(n)    2    3    5    7   11   13   17   19   23   29   31   37   41   43
%e A346425   greatest k!  2    2    2    6    6    6    6    6    6   24   24   24   24   24
%e A346425     a(n)       2    2    2    3    3    3    3    3    3    4    4    4    4    4
%o A346425 (PARI) a(n) = my(k=1); until (k! > prime(n), k++); k-1; \\ _Michel Marcus_, Jul 19 2021
%Y A346425 Cf. A000040, A061232, A136437.
%K A346425 nonn
%O A346425 1,1
%A A346425 _Bernard Schott_, Jul 16 2021