A281925 Numbers that are the product of exactly 4 primes and are of the form prime(k) + prime(k + 1).

24, 36, 60, 84, 90, 100, 152, 198, 204, 210, 276, 308, 330, 340, 372, 390, 462, 472, 492, 532, 558, 564, 712, 726, 740, 798, 852, 872, 930, 966, 1012, 1148, 1164, 1180, 1192, 1208, 1220, 1230, 1236, 1284, 1290, 1410, 1460

Offset: 1

Author

Zak Seidov, Feb 02 2017

Keywords

• nonn

Comments

Most but not all terms are multiples of 4.

Intersection of A001043 and A014613. - Bruno Berselli, Feb 02 2017

Examples

			24 = 2^3 * 3 = 11 + 13, 36 = 2^2 * 3^2 = 17 + 19, 60 = 2^2 * 3 * 5 = 29 + 31.
		

Crossrefs

Cf. A001043, A014613.

Cf. A105936 (products of exactly 3 primes).

Programs

Magma

/* From the second comment: */
a:={n: n in [2..1500] | &+[p[2]: p in Factorization(n)] eq 4};
b:={p+NextPrime(p): p in PrimesUpTo(800)};
a meet b; // Bruno Berselli, Feb 02 2017

Mathematica

Total[#] & /@ Select[Partition[Prime[Range[200]], 2, 1], 4 == PrimeOmega[Total[#]] &]