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%I #14 Jan 31 2024 19:31:18
%S 31,61,73,151,271,293,337,401,433,491,547,571,577,601,743,761,839,911,
%T 1033,1039,1063,1201,1231,1291,1321,1409,1453,1531,1571,1621,1627,
%U 2003,2017,2039,2131,2243,2273,2341,2383,2551,2663,2713,2719,2791,3041,3049
%N Primes p = p_(n+1) such that p_n + p_(n+2) = 2*p_(n+1) + 4.
%C Primes that are first prime chords.
%C These come from music based on the prime differences where the chords are an even number of note steps from the primary note.
%H Robert Israel, <a href="/A095672/b095672.txt">Table of n, a(n) for n = 1..10000</a>
%e 31 is a term because 29+37 = 2*31 + 4 = 66.
%p primes:= select(isprime,[seq(i,i=3..10000,2)]):
%p L:= primes[1..-3]+primes[3..-1]-2*primes[2..-2]:
%p primes[select(t -> L[t-1]=4,[$2..nops(L)+1])]; # _Robert Israel_, Jun 28 2018
%t m = 1; Prime[1 + Select[ Range[450], Prime[ # + 2] - 2*Prime[ # + 1] + Prime[ # ] - 4*m == 0 &]] (* _Robert G. Wilson v_, Jul 14 2004 *)
%t Select[Partition[Prime[Range[500]],3,1],#[[1]]+#[[3]]==2#[[2]]+4&][[;;,2]] (* _Harvey P. Dale_, Jan 31 2024 *)
%Y Cf. A095419, A095420, A095648, A095649, A095650, A095651, A095673.
%K nonn
%O 1,1
%A _Roger L. Bagula_, Jul 02 2004
%E Edited by _Robert G. Wilson v_, Jul 14 2004
%E Description corrected by _N. J. A. Sloane_, Jul 19 2004
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