A287793 Eight steps forward, seven steps back.

0, 1, 2, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 3, 4, 5, 6, 7, 8, 9, 10, 9, 8, 7, 6, 5, 4, 3, 4, 5, 6, 7, 8, 9, 10, 11, 10, 9, 8, 7, 6, 5, 4, 5, 6, 7, 8, 9, 10, 11, 12, 11, 10, 9, 8, 7, 6, 5, 6, 7, 8, 9, 10, 11

Offset

0,3

Links

Table of n, a(n) for n=0..81.

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

Formula

a(n) = Sum_{i=1..n} (-1)^floor((2*i-2)/15).

a(n) = a(n-1) + a(n-15) - a(n-16) for n > 15.

Maple

A287793:=n->add((-1)^floor((2*i-2)/15), i=1..n): seq(A287793(n), n=0..200);

Mathematica

Table[Sum[(-1)^Floor[(2 i - 2)/15], {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).

Cf. A287655 (seven steps forward, six steps back).

Sequence in context: A363776 A279319 A171890 * A073795 A017893 A017883

Adjacent sequences: A287790 A287791 A287792 * A287794 A287795 A287796

Keyword

nonn,easy

Author

Wesley Ivan Hurt, May 31 2017

Status

approved