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 A091633 #23 Jul 21 2025 18:37:56 %S A091633 3,7,11,13,17,19,31,37,71,73,79,97,113,131,137,139,173,179,191,193, %T A091633 197,199,311,313,317,331,337,373,379,397,719,733,739,773,797,911,919, %U A091633 937,971,977,991,997,1117,1171,1193,1319,1373,1399,1733,1777,1913,1931,1933 %N A091633 Primes having only {1, 3, 7, 9} as digits. %C A091633 Some primes of sufficient length might be termed DNA primes if the sequence of digits 1,3,7,9 in any order happens to be an appropriate analog of the DNA bases A, G, C, T. It would be interesting to know if it is possible for any DNA sequence to match a DNA prime. %H A091633 Pierre Cami and Reinhard Zumkeller, <a href="/A091633/b091633.txt">Table of n, a(n) for n = 1..10000</a> (first 5058 terms from Pierre Cami) %H A091633 <a href="/index/Pri#PrimesWithDigits">Index to entries for primes with digits in a given set</a> %F A091633 Select primes having digits 1, 3, 7, 9 only. %F A091633 a(n) = A000040(A091871(n)). - _R. J. Mathar_, Aug 29 2018 %t A091633 Select[Flatten[Table[FromDigits/@Tuples[{1,3,7,9},n],{n,4}]],PrimeQ] (* _Harvey P. Dale_, Jun 26 2015 *) %o A091633 (Haskell) %o A091633 a091633 n = a091633_list !! (n-1) %o A091633 a091633_list = filter ((== 1) . a010051') a136333_list %o A091633 -- _Reinhard Zumkeller_, Jul 17 2014 %Y A091633 Subsequence of A136333, A245193, and A030096. %Y A091633 A091871 gives prime index. %Y A091633 Cf. A010051. %K A091633 easy,nonn,base %O A091633 1,1 %A A091633 _Enoch Haga_, Jan 26 2004