A287655 Seven steps forward, six steps back.

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

Links

Table of n, a(n) for n=0..82.

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,0,0,0,0,0,0,0,0,1,-1).

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

Adjacent sequences: A287652 A287653 A287654 * A287656 A287657 A287658

Keyword

nonn,easy

Author

Wesley Ivan Hurt, May 29 2017

Status

approved