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A372600 Least prime whose decimal representation has n distinct substrings which are also prime.

%I A372600 #27 Oct 30 2024 12:18:23
%S A372600 2,13,23,113,131,137,1013,1031,1279,1237,1973,6173,10139,10193,10391,
%T A372600 10739,10937,12739,12379,36137,100937,101693,102931,102397,103913,
%U A372600 106319,106937,109379,123479,123973,125791,123719,361973,852937,1006937,1019731,1023173,1021973,1024379,1027319
%N A372600 Least prime whose decimal representation has n distinct substrings which are also prime.
%C A372600 First occurrence n of pi(a(n)) in A039994: 1, 6, 9, 30, 32, 33, 170, 173, 207, 203, 298, 804, ..., .
%H A372600 Robert G. Wilson v, <a href="/A372600/b372600.txt">Table of n, a(n) for n = 1..688</a>
%e A372600 A039994(1) = 1, is the first occurrence of 1 which is the index of the prime 2;
%e A372600 A039994(6) = 2, is the first occurrence of 2 and 6 is the index of the prime 13;
%e A372600 A039994(9) = 3, is the first occurrence of 3 and 9 is the index of the prime 23;
%e A372600 A039994(30) = 4, is the first occurrence of 4 and 30 is the index of the prime 113; etc.
%t A372600 f[p_] := Count[ PrimeQ[ Union[ FromDigits@# & /@ Rest@ Subsets[ IntegerDigits@ p]]], True]; t[_] := 0; p = 2; While[p < 10000001, a = f@ p; If[ t[a] == 0, t[a] = p]; p = NextPrime@ p]; t /@ Range@ 56
%Y A372600 Cf. A039994.
%K A372600 base,nonn
%O A372600 1,1
%A A372600 _Robert G. Wilson v_, May 06 2024