A379344 a(n) is the sum of all numbers k such that the greatest prime factor of k^2 - 1 is prime(n).

3, 31, 310, 15055, 30433, 318914, 1378856, 41139929, 29628346, 706390476, 5330866189, 17573061167, 227644494516, 912323845104, 3312744735567, 6366920047986, 69033389180772, 89835379146224, 45938747179900, 564448183072697, 6856082910702485, 19187647510345764511, 56226662050090628, 357824287346707561, 139924756071743686

Offset: 1

Author

Andrew Howroyd, Dec 21 2024

Keywords

• nonn

Comments

See A175607 and A223701 for additional information.

Crossrefs

Row sums of A223701.

Cf. A175607.

Formula

a(n) = Sum_{i>=1} A223701(n,i).