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A270189
Numbers n for which (prime(n+1)-prime(n)) is not a multiple of three.
10
1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 13, 14, 17, 19, 20, 22, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 38, 41, 42, 43, 44, 45, 48, 49, 50, 52, 53, 57, 59, 60, 61, 62, 63, 64, 65, 66, 68, 69, 70, 72, 75, 77, 78, 79, 80, 81, 82, 83, 85, 87, 88, 89, 90, 92, 93, 94, 95, 98, 101, 104, 106, 109, 112, 113, 115, 116, 117, 120, 122, 124, 125
OFFSET
1,2
COMMENTS
See A269364 for the effect of the bias that favors these terms over the terms of A270190.
LINKS
Terence Tao, Biases between consecutive primes, blog entry March 14, 2016
FORMULA
Other identities. For all n >= 1:
A269849(a(n)) = n.
MATHEMATICA
Select[Range@ 125, Mod[Prime[# + 1] - Prime@ #, 3] != 0 &] (* Michael De Vlieger, Mar 17 2016 *)
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A270189 (NONZERO-POS 1 1 A137264))
(PARI) isok(n) = ((prime(n+1) - prime(n)) % 3) != 0; \\ Michel Marcus, Mar 17 2016
CROSSREFS
Complement: A270190.
Disjoint union of A270191 and A270192.
Positions of 1's and 2's in A137264.
Left inverse: A269849.
Sequence in context: A263977 A335040 A270427 * A257672 A285314 A080544
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 16 2016
STATUS
approved