This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A364147 #12 Aug 12 2023 00:43:34 %S A364147 101,677,743,811,907,1039,1109,1129,1301,1373,1381,1567,1789,1931, %T A364147 1949,1979,2029,2447,2621,2663,2731,2879,2909,2971,3119,3187,3221, %U A364147 3319,3529,3631,3677,3803,3823,3943,4201,4253,4549,4597,4637,4643,4649,4801,4951,5119,5189,5431,5987,6053,6151,6311 %N A364147 Prime numbers that are the exact average of five consecutive odd semiprimes. %H A364147 Robert Israel, <a href="/A364147/b364147.txt">Table of n, a(n) for n = 1..10000</a> %e A364147 101 is a term because (91 + 93 + 95 + 111 + 115)/5 = 101 is prime. %e A364147 743 is a term because (737 + 737 + 745 + 749 + 753)/5 = 743 is prime. %p A364147 N:= 10^4: # for terms involving semiprimes up to N %p A364147 OSP:= select(t -> numtheory:-bigomega(t) = 2, [seq(i,i=1..N,2)]): %p A364147 select(t -> t::integer and isprime(t), add(OSP[i..-6+i],i=1..5)/5); # _Robert Israel_, Aug 11 2023 %t A364147 Select[Mean /@ Partition[Select[Range[1, 6500, 2], PrimeOmega[#] == 2 &], 5, 1], PrimeQ] (* _Amiram Eldar_, Jul 11 2023 *) %Y A364147 Cf. A000040, A046315. %Y A364147 Cf. A363074, A363187, A363188, A364148, A364149. %K A364147 nonn %O A364147 1,1 %A A364147 _Elmo R. Oliveira_, Jul 10 2023