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%I #7 Jan 18 2024 16:08:48
%S 1,2,5,7,10,11,15,21,0,22,23,31,34,38,35,45,50,46,47,53,62,58,59,67,
%T 69,84,70,71,79,83,87,92,93,101,94,105,95,106,107,116,117,122,118,125,
%U 119,134,135,139,146,142,149,143,156,155,158,159,171,166,167,176,175,185
%N Least number k such that the number of primes of the form [k/j] for j=1..k (A068050) is n, or zero if impossible.
%C a(n) = 0 for n = 8, 94, 103, 122, 180, 283, 311, 353, 355, 398, ...
%t f[n_] := Count[ PrimeQ[ Floor[ n/Table[i, {i, Floor[n/2]} ]]], True]; a = Table[0, {100} ]; Do[b = f[n]; If[b < 100 && a[[b + 1]] == 0, a[[b + 1]] = n], {n, 1, 300}]; a
%Y Cf. A068050.
%K nonn
%O 0,2
%A _Robert G. Wilson v_, Feb 12 2002
%E Name corrected by _Sean A. Irvine_, Jan 18 2024
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