A364149 - OEIS

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A364149

Prime numbers that are the exact average of seven consecutive odd semiprimes.

31, 41, 617, 677, 937, 947, 1637, 1931, 1979, 2221, 2341, 2447, 2647, 2857, 3373, 3583, 3673, 3823, 3967, 4027, 4049, 4229, 4259, 4339, 4421, 4649, 4861, 4931, 5051, 5179, 5399, 5407, 5507, 5521, 5573, 5987, 6047, 6131, 6143, 6311, 6337, 6703, 6737, 7417, 7717, 7723, 7901, 8059, 8069, 8231, 8647

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

31 is a term because (15 + 21 + 25 + 33 + 35 + 39 + 49)/7 = 31 is prime.

617 is a term because (591 + 597 + 611 + 623 + 629 + 633 + 635)/7 = 617 is prime.

MATHEMATICA

Select[Mean /@ Partition[Select[Range[1, 9000, 2], PrimeOmega[#] == 2 &], 7, 1], PrimeQ] (* Amiram Eldar, Jul 11 2023 *)

CROSSREFS

Cf. A000040, A046315.