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%I #36 Jul 29 2021 11:49:28
%S 4,6,6,14,10,20,12,28,6,36,8,34,6,14,22,18,26,16,24,36,78,8,28,74,36,
%T 30,24,16,26,148,6,12,24,24,144,8,22,8,28,66,74,46,14,10,20,106,26,28,
%U 6,120,14,66,16,24,68,76,12,60,24,30,36,48,12,30,8,16,90,30
%N First differences of A088176.
%C Conjecture: each term > 4 appears at least twice.
%C Every term of the sequence is even, because every term is a difference of two odd primes.
%F a(n) = A088176(n+2) - A088176(n+1).
%e a(7) = A088176(9) - A088176(8) = 107 - 79 = 28.
%e p = 14855077 and q = 14856077 are prime numbers such that the respective preceding prime number is the greater of twin primes. No other prime number between p and q has this property. Thus 1000 is a term of the sequence.
%t Differences[NextPrime/@Select[Prime@Range[500],NextPrime[#,-1]==#-2&]] (* _Giorgos Kalogeropoulos_, Jul 28 2021 *)
%Y Cf. A088176.
%K nonn,easy
%O 1,1
%A _Luca Santarsiero_, Jul 28 2021
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