A335076 Numbers that are the sum of two consecutive semiprimes and also the sum of two consecutive 3-almost primes.

47, 95, 115, 134, 151, 201, 233, 285, 301, 335, 346, 368, 461, 513, 527, 541, 576, 640, 713, 787, 801, 810, 864, 907, 935, 944, 1104, 1160, 1225, 1245, 1255, 1360, 1397, 1471, 1513, 1521, 1574, 1620, 1692, 1740, 1775, 1782, 1831, 1867, 1873, 1913, 1967, 2009

Offset

1,1

Comments

Apparently the sequence is infinite.

Links

Zak Seidov, Table of n, a(n) for n = 1..26539 (all terms up to 10^6).

Example

47 = 22 + 25 = A118717(8) = A001358(8) + A001358(9), and
47 = 20 + 27 = A014612(4) + A014612(5).

Mathematica

p[n_, m_] := Plus @@@ Partition[Select[Range[m], PrimeOmega[#] == n &], 2, 1]; m = 1100; Intersection[p[2, m], p[3, m]] (* Amiram Eldar, May 24 2020 *)

Crossrefs

Cf. A001358, A014612, A118717.

Sequence in context: A004943 A004963 A061153 * A044185 A044566 A349231

Adjacent sequences: A335073 A335074 A335075 * A335077 A335078 A335079

Keyword

nonn

Author

Zak Seidov, May 22 2020

Status

approved