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A269399
Numbers n for which prime(n+7)-prime(n+6) is a multiple of three.
6
3, 5, 9, 10, 12, 15, 17, 26, 30, 31, 33, 34, 40, 41, 45, 48, 49, 50, 52, 61, 65, 67, 68, 70, 78, 80, 85, 90, 91, 93, 94, 96, 97, 99, 101, 102, 104, 105, 108, 112, 113, 115, 117, 123, 124, 127, 133, 154, 155, 158, 159, 161, 162, 164, 168, 173, 174, 178, 179, 181, 182, 188, 189, 191, 193, 194, 196, 197, 199, 202, 204, 208, 210
OFFSET
1,1
LINKS
FORMULA
a(n) = A270190(n) - 6.
EXAMPLE
3 is present as the difference between A000040(3+7) = 29 and A000040(3+6) = 23 is 6, a multiple of three.
MATHEMATICA
Select[Range@ 210, Divisible[Prime[# + 7] - Prime[# + 6], 3] &] (* Michael De Vlieger, Mar 18 2016 *)
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A269399 (MATCHING-POS 1 1 (lambda (n) (= 0 (A137264 (+ 6 n))))))
(PARI) isok(n) = ((prime(n+7) - prime(n+6)) % 3) == 0; \\ Michel Marcus, Mar 18 2016
CROSSREFS
Complement: A269389.
Cf. also A270199.
Sequence in context: A316520 A153710 A230385 * A345916 A175468 A286065
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 16 2016
STATUS
approved