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A270191
Numbers n for which (prime(n+1)-prime(n)) mod 3 = 1.
5
1, 4, 6, 8, 12, 14, 19, 22, 25, 27, 29, 31, 34, 38, 42, 44, 48, 50, 53, 59, 61, 63, 65, 68, 70, 75, 78, 80, 82, 85, 88, 90, 93, 95, 101, 106, 112, 115, 117, 122, 125, 127, 131, 134, 136, 138, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 163, 169, 172, 175, 177, 181, 183, 189, 191, 193, 198, 204, 207, 211, 213, 217, 222
OFFSET
1,2
LINKS
EXAMPLE
1 is present as prime(2)-prime(1) = 3-2 = 1 = 1 mod 3.
4 is present as prime(5)-prime(4) = 11-7 = 4 = 1 mod 3.
MATHEMATICA
Select[Range@ 222, Mod[Prime[# + 1] - Prime@ #, 3] == 1 &] (* Michael De Vlieger, Mar 17 2016 *)
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A270191 (MATCHING-POS 1 1 (lambda (n) (= 1 (A137264 n)))))
(PARI) isok(n) = ((prime(n+1) - prime(n)) % 3) == 1; \\ Michel Marcus, Mar 17 2016
CROSSREFS
Subsequence of A270189.
Positions of ones in A137264.
Sequence in context: A141096 A089257 A113451 * A029709 A046458 A096629
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 16 2016
STATUS
approved