A348472 A sequence of integers from an additive problem with prime numbers.

7, 19, 49, 113, 243, 413, 675, 1083, 1773, 2899, 3541, 4251, 5031, 5883, 6807, 7805, 8877, 10025, 11247, 12545, 13919, 15373, 16903, 18511, 20199, 21965, 23813, 25741, 27749, 29839, 32009, 34263, 36599, 39019, 41521, 44107, 46777, 49531, 52369, 55293, 58303, 61397, 64577

Offset

2,1

Links

Table of n, a(n) for n=2..44.

S. I. Dimitrov, On an equation with prime numbers close to squares, arXiv:1910.04531 [math.NT], 2019.

A. Kumchev and D. Tolev, An additive problem with prime numbers from a thin set, Acta Math. Hungarica, 76, (1997), 31-43.

Formula

For n=2..10, a(n) is in [7, 19, 49, 113, 243, 413, 675, 1083, 1773]; for n>10, a(n) = 2*round(n^2*(3*log(n) + log(log(n)) + 4))-21.

Prog

(PARI) a(n) = if ((n>=2) && (n<=10), return([7, 19, 49, 113, 243, 413, 675, 1083, 1773][n-1])); 2*round(n^2*(3*log(n) + log(log(n)) + 4))-21;

Crossrefs

Sequence in context: A067651 A357301 A090025 * A003232 A018728 A027523

Adjacent sequences: A348469 A348470 A348471 * A348473 A348474 A348475

Keyword

nonn

Author

Michel Marcus, Oct 19 2021

Status

approved