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A283363
Absolute values of first differences of A090396.
1
1, 0, 0, 2, 2, 3, 3, 4, 8, 3, 1, 1, 3, 12, 0, 2, 0, 2, 2, 0, 2, 21, 3, 7, 7, 5, 5, 26, 2, 12, 12, 19, 11, 18, 14, 16, 20, 17, 21, 20, 24, 23, 23, 20, 18, 21, 15, 32, 20, 29, 21, 25, 33, 20, 36, 19, 23, 36, 24, 33, 23, 15, 47, 20, 22, 14, 54, 9, 13, 15, 15, 60, 12, 12, 14, 14, 12, 65
OFFSET
1,4
COMMENTS
See the beginning of helix in scatterplot link at Links section.
FORMULA
a(n) = abs(A090396(n+1) - A090396(n)).
EXAMPLE
a(5) = 2 because a(5) = abs(A090396(6) - A090396(5)) = abs(5 - 3) = 2.
MATHEMATICA
A[n_] := Mod[Sum[Prime[k], {k, n}], n]; Table[Abs[A[n+1] - A[n]], {n, 78}] (* Indranil Ghosh, Mar 06 2017 *)
PROG
(PARI) a090396(n) = sum(k=1, n, prime(k)) % n;
a(n) = abs(a090396(n+1) - a090396(n));
CROSSREFS
Cf. A090396.
Sequence in context: A184351 A343659 A146922 * A236210 A357416 A362251
KEYWORD
nonn,look
AUTHOR
Altug Alkan, Mar 06 2017
STATUS
approved