A091633 Primes whose digits are restricted to 1,3,7,9 (same as terminal digits of primes).

3, 7, 11, 13, 17, 19, 31, 37, 71, 73, 79, 97, 113, 131, 137, 139, 173, 179, 191, 193, 197, 199, 311, 313, 317, 331, 337, 373, 379, 397, 719, 733, 739, 773, 797, 911, 919, 937, 971, 977, 991, 997, 1117, 1171, 1193, 1319, 1373, 1399, 1733, 1777, 1913, 1931, 1933

Offset

1,1

Comments

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.

Links

Pierre Cami and Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 (first 5058 terms from Pierre Cami)

Formula

Select primes having digits 1, 3, 7, 9 only.

a(n) = A000040(A091871(n)). - R. J. Mathar, Aug 29 2018

Mathematica

Select[Flatten[Table[FromDigits/@Tuples[{1, 3, 7, 9}, n], {n, 4}]], PrimeQ] (* Harvey P. Dale, Jun 26 2015 *)

Prog

(Haskell)
a091633 n = a091633_list !! (n-1)
a091633_list = filter ((== 1) . a010051') a136333_list
-- Reinhard Zumkeller, Jul 17 2014

Crossrefs

A091871 gives prime index.

Cf. A010051, subsequence of A136333, A245193.

Sequence in context: A023236 A038920 A361822 * A166559 A177193 A089690

Adjacent sequences: A091630 A091631 A091632 * A091634 A091635 A091636

Keyword

easy,nonn,base

Author

Enoch Haga, Jan 26 2004

Status

approved