OFFSET
1,1
COMMENTS
Primes that are first prime chords.
These come from music based on the prime differences where the chords are an even number of note steps from the primary note.
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
31 is a term because 29+37 = 2*31 + 4 = 66.
MAPLE
primes:= select(isprime, [seq(i, i=3..10000, 2)]):
L:= primes[1..-3]+primes[3..-1]-2*primes[2..-2]:
primes[select(t -> L[t-1]=4, [$2..nops(L)+1])]; # Robert Israel, Jun 28 2018
MATHEMATICA
m = 1; Prime[1 + Select[ Range[450], Prime[ # + 2] - 2*Prime[ # + 1] + Prime[ # ] - 4*m == 0 &]] (* Robert G. Wilson v, Jul 14 2004 *)
Select[Partition[Prime[Range[500]], 3, 1], #[[1]]+#[[3]]==2#[[2]]+4&][[;; , 2]] (* Harvey P. Dale, Jan 31 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Jul 02 2004
EXTENSIONS
Edited by Robert G. Wilson v, Jul 14 2004
Description corrected by N. J. A. Sloane, Jul 19 2004
STATUS
approved