A245175 - OEIS

%I #26 Nov 05 2025 15:22:27

%S 14,8,40,-16,46,-44,46,68,-58,100,-66,-54,54,82,38,-204,314,-214,-64,

%T 176,-20,6,120,-72,-158,34,-58,28,680,-590,4,-2,304,-386,208,44,-180,

%U 146,-74,-114,408,-458,136,-158,652,340,-902,-66,60,42,-30,490,-466,228

%N Second differences of A038580.

%H Alois P. Heinz, <a href="/A245175/b245175.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Jens Kruse Andersen)

%H R. G. Batchko, <a href="https://arxiv.org/abs/1405.2900">A prime fractal and global quasi-self-similar structure in the distribution of prime-indexed primes</a>, arXiv preprint arXiv:1405.2900, 2014. See Table 2.

%p a:= ((f-> n-> f(n+1)-f(n))@@2)(ithprime@@3):

%p seq(a(n), n=1..60);

%t Differences[Nest[Prime, Range[60], 3], 2] (* _Jean-François Alcover_, Oct 06 2018 *)

%o (PARI) f(n) = prime(prime(prime(n)))

%o a(n) = f(n+2)-2*f(n+1)+f(n)

%o vector(50, n, a(n)) \\ _Jens Kruse Andersen_, Jul 18 2014

%Y Cf. A038580.

%K sign

%O 1,1

%A _N. J. A. Sloane_, Jul 17 2014