A134990 Interleave two arithmetic progressions 8,10,12,14,... and 15,13,11,9,... of differences +2 and -2 respectively.

8, 15, 10, 13, 12, 11, 14, 9, 16, 7, 18, 5, 20, 3, 22, 1, 24, -1, 26, -3, 28, -5, 30, -7, 32, -9, 34, -11, 36, -13, 38, -15, 40, -17, 42, -19, 44, -21, 46, -23, 48, -25, 50, -27, 52, -29, 54, -31, 56, -33, 58, -35, 60, -37, 62, -39, 64, -41, 66, -43, 68, -45, 70, -47, 72, -49, 74, -51, 76, -53, 78, -55, 80, -57, 82, -59, 84, -61

Offset

1,1

References

Terry H. Stickels, Mesmerizing Mind-Bending Puzzles, Sterling Publishing Company, Inc. 2002. Page 21

Links

Table of n, a(n) for n=1..78.

Formula

O.g.f.: -x(17x^2+23x+8)/[(1+x)^2*(-1+x)]. - R. J. Mathar, Feb 06 2008

Mathematica

Table[If[OddQ[n], n + 7, 17 - n], {n, 1, 60}] (* Stefan Steinerberger, Feb 07 2008 *)
With[{nn=80}, Riffle[Range[8, 6+nn, 2], Range[15, 17-nn, -2]]] (* Harvey P. Dale, Jun 19 2014 *)

Crossrefs

Sequence in context: A082170 A136377 A103706 * A126852 A248389 A301618

Adjacent sequences: A134987 A134988 A134989 * A134991 A134992 A134993

Keyword

sign

Author

Kate Ross (rossk1111(AT)yahoo.com), Feb 05 2008

Extensions

More terms from R. J. Mathar and Stefan Steinerberger, Feb 06 2008

Status

approved