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%I #11 Jan 09 2020 03:07:28
%S 5,11,17,31,41,59,109,179,191,283,599,859,1063,1153,1723,2081,2341,
%T 3001,3259,3299,4421,4549,4787,4933,6361,6661,8221,8233,8389,10009,
%U 10457,10861,13693,13709,16141,16693,16901,17387,17659,20441,20477,20773
%N Twin-prime-indexed primes (TWIPS): members of a pair of twin primes whose prime index is also a member of a pair of twin primes.
%C If there are infinitely many twin primes, this sequence has an infinite number of terms.
%H Amiram Eldar, <a href="/A087373/b087373.txt">Table of n, a(n) for n = 1..10000</a>
%e 17 is a twin prime paired with 19. The 17th prime is 59 which is also a twin prime paired with 61.
%o (PARI) twips(n) = { forprime(x=3,n, x1=prime(x); if(isprime(x-2) || isprime(x+2), if(isprime(x1-2) || isprime(x1+2), print1(x1",") ) ) ) }
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Oct 21 2003
%E Offset corrected by _Amiram Eldar_, Jan 09 2020