login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

Smallest member of a pair of consecutive twin prime pairs that have two primes between them.
1

%I #7 Dec 28 2019 07:47:52

%S 41,197,281,599,641,827,857,1061,1451,2237,2549,3119,3329,3821,4001,

%T 4091,5417,5441,5849,6269,6659,6791,7457,7949,8387,8597,9239,9677,

%U 10301,10427,10859,10889,11117,11717,11939,12071,13337,13721,13931

%N Smallest member of a pair of consecutive twin prime pairs that have two primes between them.

%H Amiram Eldar, <a href="/A089634/b089634.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) pbetweentw(n,p) = \p is the number of primes between { forstep(x1=1,n,1, c=0; t1 = twin[x1]; t2 = twin[x1+1]; for(y=t1+4,t2-1, if(isprime(y),c++) ); if(c==p,print1(t1",")) ) } savetwins(n) = \ build a twin prime table of lower bounds { twin = vector(n); c=1; forprime(x=3,n*10, if(isprime(x+2), twin[c]=x; c++; ) )

%K easy,nonn

%O 1,1

%A _Cino Hilliard_, Jan 01 2004

%E Offset corrected by _Amiram Eldar_, Dec 28 2019