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 A140959 Number of distinct-digit primes in base n. 0
 0, 1, 6, 6, 31, 130, 632, 4418, 34401, 283086, 2586883, 28637741 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE a(1) = 0; a(2) = 1 since only the prime 2 in base 2 has distinct integers, 10_2; a(3) = 6 since the primes {2, 3, 5, 7, 11 & 19} in base 3 have distinct integers, {2_3, 10_3, 12_3, 21_3, 102_3, 201_3}; etc. a(10) = 283086 because it is the partial sum of A073532. MATHEMATICA f[b_] := Block[{c = 0, k = 1, lmt = b^b}, While[p = Prime@ k; p < lmt, k++; If[ Union[ Length /@ Split@ Sort@ IntegerDigits[p, b]] == {1}, c++ ]]; c]; Array[f, 6] PROG (Sage) def a(n):     return sum(len(p.digits(n)) == len(set(p.digits(n))) for p in prime_range(n^n)) # Eric M. Schmidt, Oct 26 2014 CROSSREFS Cf. A073532. Sequence in context: A279865 A321528 A074002 * A015699 A244416 A165827 Adjacent sequences:  A140956 A140957 A140958 * A140960 A140961 A140962 KEYWORD nonn,base,hard,more AUTHOR Robert G. Wilson v, Jul 25 2008 EXTENSIONS a(11)-a(12) from Eric M. Schmidt, Oct 29 2014 STATUS approved

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Last modified April 13 15:23 EDT 2021. Contains 342936 sequences. (Running on oeis4.)