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A131695
a(n) = 0 iff 2*prime(n+1) = prime(n) + prime(n+2), otherwise a(n) = 1.
1
1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1
OFFSET
1,1
FORMULA
a(n) = A098726(n) - 2. - Filip Zaludek, Dec 16 2016
MATHEMATICA
Table[Boole[2 Prime[n + 1] != Prime@ n + Prime[n + 2]], {n, 120}] (* Michael De Vlieger, Dec 17 2016 *)
PROG
(PARI) A131695(n) = ((2*prime(1+n)) != (prime(n)+prime(2+n))); \\ Antti Karttunen, Aug 30 2017
CROSSREFS
Cf. A001223, A122535, A064113 (positions of zeros).
Sequence in context: A013596 A182394 A079054 * A324113 A105812 A134323
KEYWORD
nonn
AUTHOR
Giovanni Teofilatto, Sep 15 2007
EXTENSIONS
Definition and values corrected, keyword:cons removed; R. J. Mathar, Apr 22 2010
STATUS
approved