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A348472
A sequence of integers from an additive problem with prime numbers.
0
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
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
KEYWORD
nonn
AUTHOR
Michel Marcus, Oct 19 2021
STATUS
approved