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.
Reap[For[p = 23, p < 50000, p = q, q = NextPrime[p]; If[q == p + 6 && Max[ FactorInteger[#][[1, 1]]& /@ Range[p+1, q-1]] == 19, Sow[p]]]][[2, 1]] (* Jean-François Alcover, Jan 29 2018 *)
f[p_] := Max[FactorInteger[#][[1, 1]] & /@ Range[ p+1, NextPrime[p] - 1]]; Select[Prime@ Range@ 10300, NextPrime[#] == # + 6 && f[#] == 31 &] (* Giovanni Resta, May 30 2018 *)
Select[Prime[Range[2, 120]], (d = # - NextPrime[#, -1]) != 2^IntegerExponent[d, 2] &] (* Amiram Eldar, Jun 22 2022 *)
isp2(n) = my(p); (n==1) || (isprimepower(n, &p) && (p==2)); \\ A000079 isok(p) = isprime(p) && !isp2(p-precprime(p-1)) \\ Michel Marcus, Jun 22 2022
from itertools import islice, count from sympy import prime, prevprime def A355161_gen(): # generator of terms return filter(lambda n:((~(m:=n-prevprime(n))+1)&m)-m, (prime(n) for n in count(2))) A355161_list = list(islice(A355161_gen(),30)) # Chai Wah Wu, Aug 23 2022
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