A110792 Copies of 7,3 and 1 cyclically such that every partial concatenation is a prime.

7, 3, 1111111, 777777777, 33, 11111111111111111111111111111111111111111111111111111111111111111, 7777777777777777777, 33333333333333333333, 111111111111111111111111111111111111111

Offset

1,1

Links

Table of n, a(n) for n=1..9.

Example

7,73,731111111,...are all prime.

Crossrefs

Cf. A110793 (digit lengths).

Other combinations: A110774, A110776, A110778, A110780, A110782, A110788, A110790.

Sequence in context: A320842 A112099 A013324 * A221388 A303982 A175998

Adjacent sequences: A110789 A110790 A110791 * A110793 A110794 A110795

Keyword

base,nonn

Author

Amarnath Murthy, Aug 13 2005

Extensions

More terms from Sean A. Irvine, Mar 21 2010

a(9) from Jon E. Schoenfield, Jul 11 2010

Status

approved