A145376 If T(n)>=n is the nearest triangular number to n and p_n is the n-th prime, then a(n) is the least prime such that T(a(n)*p_n)-a(n)p_n is a triangular number.

3, 2, 2, 2, 2, 3, 5, 5, 7, 11, 11, 11, 13, 17, 17, 19, 23, 23, 23, 29, 29, 29, 31, 37, 37, 41, 41, 41, 41, 43, 53, 53, 53, 59, 59, 61, 67, 67, 67, 71, 73, 73, 79, 79, 83, 83, 89, 97, 97, 97, 97, 101, 101, 107, 107, 113, 113, 127, 127, 127, 127, 127, 131, 137

Offset: 1

Author

Vladimir Shevelev, Oct 09 2008

Keywords

• nonn

Comments

Conjecture. For n>=2 the sequence is nondecreasing.

The conjecture holds for the first 10000 terms. [Charles R Greathouse IV, Feb 21 2011]

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000217, A145043, A145016, A145281, A145300.

Extensions

a(27)-a(64) from Charles R Greathouse IV, Feb 21 2011