OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 100 terms from Zak Seidov)
EXAMPLE
a(2) = 19 = 3^2 - 3*5 + 5^2 is the only prime obtained with a pair of twin primes: (3, 5). - Bernard Schott, Dec 23 2020
MATHEMATICA
Select[Map[#1^2 - #1 #2 + #2^2 & @@ # &, Partition[Prime@ Range[610], 2, 1]], PrimeQ] (* Michael De Vlieger, Dec 13 2020 *)
PROG
(PARI) forprime(p=1, 1e4, my(q=nextprime(p+1), x=p^2-p*q+q^2); if(ispseudoprime(x), print1(x, ", "))) \\ Felix Fröhlich, Dec 14 2020
(PARI) first(n) = { my(q = 2, p, res = vector(n), t = 0); forprime(p = 3, oo, c = p^2 - p*q + q^2; if(isprime(c), t++; res[t] = c; if(t >= n, return(res) ) ); q = p; ) } \\ David A. Corneth, Dec 19 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Dec 13 2020
STATUS
approved