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A226073
Numbers k such that triangular(k)-1 is a square and triangular(k)+1 is a prime number.
2
1, 4, 148, 5821348, 13748537282247342677718148, 49900608324196518198677680899235165296598423281799348
OFFSET
1,2
COMMENTS
a(7) has 191 decimal digits: 314305920...194453348.
Corresponding primes and roots of squares: A226072 and A226074.
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, May 25 2013
STATUS
approved