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A287655
Seven steps forward, six steps back.
4
0, 1, 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 3, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 4, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 5, 6, 7, 8, 9, 10, 11, 10, 9, 8, 7, 6, 5, 6, 7, 8, 9, 10, 11, 12, 11, 10, 9, 8, 7, 6, 7, 8, 9, 10
OFFSET
0,3
FORMULA
a(n) = a(n-1) + a(n-13) - a(n-14) for n > 13.
a(n) = Sum_{i=1..n} (-1)^floor((2*i-2)/13).
MAPLE
A287655:=n->add((-1)^floor((2*i-2)/13), i=1..n): seq(A287655(n), n=0..200);
MATHEMATICA
Table[Sum[(-1)^Floor[(2 i - 2)/13], {i, n}], {n, 0, 100}]
CROSSREFS
Cf. A008611 (one step back, two steps forward).
Cf. A058207 (three steps forward, two steps back).
Cf. A260644 (four steps forward, three steps back).
Cf. A271800 (five steps forward, four steps back).
Cf. A271859 (six steps forward, five steps back).
Sequence in context: A063265 A211011 A232242 * A073794 A017892 A017882
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, May 29 2017
STATUS
approved