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%I #14 Oct 22 2021 11:21:30
%S 2,4,47,52,1374,1385,3738,3755,6680,6703,84626,84657,89480,89521,
%T 91832,91879,173092,173151,192882,192949,524587,524660,865301,865384,
%U 876543,876640,890479,890582,904273,904382,918859,918986,1628979,1629116,1647107,1647256,1666775
%N Where prime(n) first appears in A307730.
%H Chai Wah Wu, <a href="/A348247/b348247.txt">Table of n, a(n) for n = 1..134</a>
%o (Python)
%o from collections import Counter
%o from sympy import prime
%o def A348247(n):
%o c, b, p, i = Counter(), 1, prime(n), 1
%o while True:
%o k, kb = 1, b
%o while c[kb] >= kb:
%o k += 1
%o kb += b
%o if kb == p:
%o return i
%o c[kb] += 1
%o b = k
%o i += 1 # _Chai Wah Wu_, Oct 21 2021
%Y Cf. A307720, A307730, A307632, A348246.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Oct 17 2021
%E More terms from _Chai Wah Wu_, Oct 21 2021