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A105293
Smallest prime formed by reverse concatenation of n consecutive triangular numbers, 0 if no such prime exists.
0
3, 31, 631, 10631, 19531891183017701711, 665545362821, 7140702169036786667065556441, 1178111628114761132511175110261087810731, 0, 55453628211510631
OFFSET
1,1
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
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 25 2005
STATUS
approved