A362578 Prime numbers followed by two consecutive numbers which are products of four distinct primes (or tetraprimes).

8293, 16553, 17389, 18289, 22153, 26893, 29209, 33409, 35509, 36293, 39233, 39829, 40493, 41809, 45589, 48109, 58393, 59629, 59753, 59981, 60493, 60913, 64013, 64921, 65713, 66169, 69221, 71329, 74093, 75577, 75853, 77689, 77933, 79393, 79609, 82913, 84533, 85853, 87589, 87701, 88681

Offset

1,1

Links

Table of n, a(n) for n=1..41.

Example

8293 (prime), 8294 = 2*11*13*29 and 8295 = 3*5*7*79.
16553 (prime), 16554 = 2*3*31*89 and 16555 = 5*7*11*43.
17389 (prime), 17390 = 2*5*37*47 and 17391 = 3*11*17*31.

Mathematica

q[n_] := FactorInteger[n][[;; , 2]] == {1, 1, 1, 1}; Select[Prime[Range[10^4]], AllTrue[# + {1, 2}, q] &] (* Amiram Eldar, Apr 25 2023 *)

Prog

(PARI) is(n) = (omega(n)==4) && (bigomega(n)==4); \\ A046386
isok(p) = isprime(p) && is(p+1) && is(p+2); \\ Michel Marcus, Apr 25 2023

Crossrefs

Cf. A000040, A046386, A140078 and A361796.

Sequence in context: A280872 A329342 A237948 * A250991 A206192 A252155

Adjacent sequences: A362575 A362576 A362577 * A362579 A362580 A362581

Keyword

nonn

Author

Massimo Kofler, Apr 25 2023

Status

approved