A379405 a(n) = p((n+1)*p(n)), where p(x) = least prime > x; i.e., p = A151800.

3, 5, 11, 23, 29, 43, 53, 89, 101, 113, 127, 157, 173, 239, 257, 277, 293, 347, 367, 461, 487, 509, 541, 701, 727, 757, 787, 821, 853, 937, 967, 1187, 1223, 1259, 1297, 1361, 1373, 1559, 1601, 1657, 1693, 1811, 1861, 2069, 2129, 2179, 2213, 2549, 2609, 2657

Offset

0,1

Links

Michael De Vlieger, Table of n, a(n) for n = 0..10000

Formula

a(n) = A151800(A053024(n+1)). - Alois P. Heinz, Jan 18 2025

Example

p(1) = 2, so a(1) = p(2*p(1)) = 5.

Mathematica

Table[NextPrime[(n+1)*NextPrime[n]], {n, 0, 80}]

Prog

(PARI) p(n) = nextprime(n+1);
a(n) = p((n+1)*p(n)); \\ Michel Marcus, Jan 18 2025
(Python)
from sympy import nextprime
def A379405(n): return nextprime((n+1)*nextprime(n)) # Chai Wah Wu, Jan 20 2025

Crossrefs

Cf. A000040, A053024, A151800, A378135, A378136, A378137.

Sequence in context: A015915 A275785 A106901 * A154550 A023202 A049436

Adjacent sequences: A379402 A379403 A379404 * A379406 A379407 A379408

Keyword

nonn,changed

Author

Clark Kimberling, Jan 18 2025

Status

approved