A109561 prime(k) for those k where floor((2*(prime(k+1)-prime(k))*PrimePi(k) mod (8*k))/k) = m with m = 7.

199, 211, 317, 1381, 1759, 1913, 2161, 2503, 3089, 3413, 3947, 5449, 5717, 5903, 6427, 7129, 8017, 9349, 9439, 9697, 10039, 10111, 10369, 10567, 11003, 11329, 11633, 11839, 12073, 12119, 13009, 13267, 16007, 16033, 16193, 16453, 16493, 16703, 16763, 16787, 17053

Offset: 1

Author

Roger L. Bagula, Jun 27 2005

Keywords

• nonn
• less

Crossrefs

Cf. A000040, A000720, A001359.

Cf. A109556-A109569 for m = 2..15.

Programs

Mathematica

a = Flatten[Table[If[Floor[2*Mod[(Prime[n + 1] - Prime[n])*PrimePi[n]/n, 8]] == 7, Prime[n], {}], {n, 1, 400}]]

Extensions

Name edited, offset corrected and more terms added by Amiram Eldar, Jun 02 2025