cp's OEIS Frontend

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.

A335737 a(n) is the smallest prime p such that 2p+3q and 3p+2q are n-almost primes, where q is next prime after p.

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%I A335737 #22 Jun 24 2020 03:13:13
%S A335737 5,47,139,2521,77269,631459,6758117,33059357,7607209367,173030234371,
%T A335737 152129921851
%N A335737 a(n) is the smallest prime p such that 2p+3q and 3p+2q are n-almost primes, where q is next prime after p.
%e A335737 Both 2*5+3*7 = 31 and 3*5 +2*7 = 29 are primes.
%e A335737 Both 2*47+3*53 = 253 = 11*23 and 3*47+2*53 = 247 = 13*19 are semiprimes.
%t A335737 m = 6; s = Table[0, {m}]; p = 2; c = 0; While[c < m, q = NextPrime[p]; If[(o = PrimeOmega[2 p + 3 q]) ==  PrimeOmega[ 3 p + 2 q] && o <= m && s[[o]] == 0, c++; s[[o]] = p]; p = q]; s (* _Amiram Eldar_, Jun 23 2020 *)
%o A335737 (PARI) for(n=1,8,my(p=2); forprime(q=3, oo, my(pq=2*p+3*q, qp=3*p+2*q); if(bigomega(pq)==n, if(bigomega(qp)==n, print1(p, ", "); break));p=q)) \\ _Hugo Pfoertner_, Jun 24 2020
%Y A335737 Cf. A000040, A001358, A014612, A014613, A014614, A078840.
%K A335737 nonn,more
%O A335737 1,1
%A A335737 _Zak Seidov_, Jun 20 2020
%E A335737 a(10)-a(11) from _Amiram Eldar_, Jun 23 2020