A281926 Numbers that are the product of exactly 5 primes and are of the form prime(k) + prime(k + 1).

112, 120, 162, 300, 396, 450, 456, 520, 630, 684, 696, 702, 752, 828, 882, 918, 924, 990, 1044, 1064, 1140, 1250, 1272, 1300, 1428, 1530, 1650, 1692, 1710, 1716, 1740, 1900, 2032, 2072, 2124, 2156

Offset

1,1

Comments

Note that there is no case of 2 primes.

Intersection of A001043 and A014614. - Bruno Berselli, Feb 02 2017

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

112 = 2^4 * 7 = 53 + 59, 120 = 2^3 * 3 * 5 = 59 + 61, 162 = 2 * 3^4 = 79 + 83.

Mathematica

Total[#] & /@ Select[Partition[Prime[Range[1000]], 2, 1], 5 == PrimeOmega[Total[#]] &]

Prog

(PARI) list(lim)=my(v=List()); forprime(p=2, lim\16, forprime(q=2, min(lim\(8*p), p), forprime(r=2, min(lim\(4*p*q), q), forprime(s=2, min(lim\(2*p*q*r), r), my(t=2*p*q*r*s); if(nextprime(t/2)+precprime(t/2)==t, listput(v, t)))))); Set(v) \\ Charles R Greathouse IV, Feb 05 2017

Crossrefs

Cf. A001043, A014614.

Cf. A105936 (products of 3 primes), A281925 (products of 4 primes).

Sequence in context: A262521 A096680 A109383 * A036301 A117723 A359142

Adjacent sequences: A281923 A281924 A281925 * A281927 A281928 A281929

Keyword

nonn

Author

Zak Seidov, Feb 02 2017

Status

approved