A105293 Smallest prime formed by reverse concatenation of n consecutive triangular numbers, 0 if no such prime exists.

3, 31, 631, 10631, 19531891183017701711, 665545362821, 7140702169036786667065556441, 1178111628114761132511175110261087810731, 0, 55453628211510631

Offset

1,1

Links

Table of n, a(n) for n=1..10.

Example

a(3)=631 because 631 is the smallest prime formed by reverse concatenation of 3 consecutive triangular numbers i.e. 1,3 and 6.

Crossrefs

Sequence in context: A370260 A222895 A373754 * A377746 A368489 A104841

Adjacent sequences: A105290 A105291 A105292 * A105294 A105295 A105296

Keyword

base,nonn

Author

Shyam Sunder Gupta, Apr 25 2005

Status

approved