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A192203
Numbers k such that k, k+1, and k+2 are each the product of exactly 5 distinct primes.
7
16467033, 18185869, 21134553, 21374353, 21871365, 22247553, 22412533, 22721585, 24845313, 25118093, 25228929, 25345333, 25596933, 26217245, 27140113, 29218629, 29752345, 30323733, 30563245, 31943065, 32663265, 33367893, 36055045, 38269021, 39738061, 40547065
OFFSET
1,1
COMMENTS
Numbers k such that k, k+1, and k+2 are all members of A046387. - N. J. A. Sloane, Jul 17 2024
A subsequence of A242608 intersect A016813. - M. F. Hasler, May 19 2014
All terms are congruent to 1 mod 4. - Zak Seidov, Dec 22 2014
EXAMPLE
a(1)=16467033 because it is the product of 5 distinct primes (3,11,17,149,197), and so are a(1)+1: 16467034 (2,19,23,83,227), and a(1)+2: 16467035 (5,13,37,41,167).
MATHEMATICA
SequencePosition[Table[If[PrimeNu[n]==PrimeOmega[n]==5, 1, 0], {n, 164*10^5, 406*10^5}], {1, 1, 1}][[;; , 1]]+164*10^5-1 (* Harvey P. Dale, Jul 17 2024 *)
PROG
(PARI) forstep(n=1+10^7, 1e8, 4, for(k=n, n+2, issquarefree(k)||next(2)); for(k=n, n+2, omega(k)==5||next(2)); print1((n)", ")) \\ M. F. Hasler, May 19 2014
CROSSREFS
Cf. A046387, A140079. Subsequence of A318964 and of A364266.
Sequence in context: A216004 A155949 A355095 * A248204 A365812 A178555
KEYWORD
nonn
AUTHOR
Gil Broussard, Jun 25 2011
STATUS
approved