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%I #16 Mar 31 2019 00:18:31
%S 1,2,3,11,23,113,425,1912,11872,57918,303157,1757094
%N Let u be any string of n digits from {0,...,7}; let f(u) = number of distinct primes, not beginning with 0, formed by permuting the digits of u; then a(n) = max_u f(u).
%e a(2)=2 because 15 and 51 (written in base 8) are primes (13 and 41).
%e a(3)=3 because 531, 351 and 513 (in base 8) are primes (107, 233, 331), or 145, 415 and 541 (in base 8) are primes (101, 269, 353), or 147, 417 and 471 are primes (103, 271, 313) etc. _R. J. Mathar_, Apr 23 2016
%t c[x_] := Module[{},
%t Length[Select[Permutations[x],
%t First[#] != 0 && PrimeQ[FromDigits[#, 8]] &]]];
%t A065849[n_] := Module[{i},
%t Return[Max[Map[c, DeleteDuplicatesBy[Tuples[Range[0, 7], n],
%t Table[Count[#, i], {i, 0, 7}] &]]]]];
%t Table[A065849[n], {n, 1, 7}] (* _Robert Price_, Mar 30 2019 *)
%Y Cf. A065843, A065844, A065845, A065846, A065847, A065848, A065850, A065851, A065852, A065853
%K base,more,nonn
%O 1,2
%A _Sascha Kurz_, Nov 24 2001
%E 2 more terms from _Sean A. Irvine_, Sep 06 2009
%E Definition corrected by _David A. Corneth_, Apr 23 2016
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