A231442 The digits of a(n) and a(n+1) taken together are the digits of a prime; least permutation of the positive integers with this property.

1, 3, 2, 9, 5, 11, 8, 12, 4, 7, 6, 10, 13, 15, 14, 17, 18, 16, 19, 21, 22, 30, 20, 23, 24, 29, 26, 27, 25, 31, 28, 33, 32, 35, 36, 34, 37, 39, 38, 41, 42, 43, 45, 47, 44, 51, 40, 49, 46, 57, 50, 53, 48, 59, 56, 63, 52, 61, 54, 67, 55, 69, 58, 70, 60, 71, 62, 72, 64, 73, 66, 79, 75, 65, 74, 68, 77

Offset: 1

Author

M. F. Hasler, Nov 09 2013

Keywords

• nonn
• base

Examples

			Start with a(1)=1. The same number cannot be used twice, so the least prime that can be made with this digit is 13, so a(2)=3.
		

Links

• Lars Blomberg, Table of n, a(n) for n = 1..10000
• M. F. Hasler, in reply to E. Angelini, Two make a prime, SeqFan list, Nov 09 2013

Crossrefs

Cf. A231433 (analog for nonnegative integers).

Programs

PARI

{a=1;u=0;for(n=1,99,u+=1<"0"&&(a=k)&&next(3))))}