A110776 Copies of 1 and 7 alternately such that every partial concatenation is a prime.

11, 777, 11, 777777, 111111111, 7777777777777777777777777, 111111111, 777

Offset

1,1

Links

Table of n, a(n) for n=1..8.

Example

11, 11777, 1177711, ... are all prime.

Crossrefs

Cf. A110774, A110775, A110777, A110778, A112534, A110780, A110781, A110782, A110783, A110788, A110789.

Sequence in context: A267908 A180740 A330309 * A058392 A100369 A196426

Adjacent sequences: A110773 A110774 A110775 * A110777 A110778 A110779

Keyword

base,nonn

Author

Amarnath Murthy, Aug 12 2005

Extensions

Corrected and extended by Joshua Zucker, Jan 11 2006

The next term has 762 1's and is too large to include.

Status

approved