This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A239685 #6 May 31 2019 20:35:30 %S A239685 263,2063,4463,4643,6203,20063,26003,60443,62003,64403,68483,69929, %T A239685 86843,88463,88643,92699,200063,260003,260999,296099,296909,400643, %U A239685 406403,406883,446003,449699,460403,464003,464999,468803,488603,494699,496499,496949,499649 %N A239685 Prime numbers for which the sum of reciprocals of nonzero digits equals 1. %C A239685 Primes in A214959. %C A239685 Property of the sequence: a(n) == 3 or 9 (mod 10). If n contains nonzero digits, each number > 263 contains at least two identical digits, and the subsequence of the corresponding sum of reciprocals of digits (primes in A037268) is finite. %e A239685 2063 is in the sequence because 1/2 + 1/6 + 1/3 = 1. %p A239685 with(numtheory):nn:=500000:for m from 1 to nn do:n:=ithprime(m):y:=convert(n,base,10):n2:=nops(y):s:=0:for i from 1 to n2 do: if y[i]<>0 then s:=s+1/y[i]:else fi:od:if s=1 then printf(`%d, `,n):else fi:od: %t A239685 Select[Prime[Range[42000]],Total[1/Select[IntegerDigits[#],#!=0&]]==1&] (* _Harvey P. Dale_, May 31 2019 *) %Y A239685 Cf. A037268, A214959. %K A239685 nonn,base %O A239685 1,1 %A A239685 _Michel Lagneau_, Mar 24 2014