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Interleave two arithmetic progressions 8,10,12,14,... and 15,13,11,9,... of differences +2 and -2 respectively.
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%I #7 Sep 16 2015 13:34:48

%S 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,

%T -9,34,-11,36,-13,38,-15,40,-17,42,-19,44,-21,46,-23,48,-25,50,-27,52,

%U -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

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

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

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

%t Table[If[OddQ[n], n + 7, 17 - n], {n, 1, 60}] (* _Stefan Steinerberger_, Feb 07 2008 *)

%t With[{nn=80},Riffle[Range[8,6+nn,2],Range[15,17-nn,-2]]] (* _Harvey P. Dale_, Jun 19 2014 *)

%K sign

%O 1,1

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

%E More terms from _R. J. Mathar_ and _Stefan Steinerberger_, Feb 06 2008