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A129000
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Start with an integer (in this case 1). First, add 5 or 8 if the integer is odd or even, respectively. Then divide by 2.
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0
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1, 3, 4, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7, 6, 7
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Tanya Khovanova Arithmetic Progressions
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FORMULA
| a(n)=[a(n-1) + b]/d, if a(n) even =[a(n-1) + c]/d, if a(n) odd (starting a(1)=1 with b=5, c=8, d=2)
a(n)=[13-(-1)^n]/2-6*[C(2*(n-1),(n-1)) mod 2]-3*{C[n^2,n+2] mod 2}-3*[C((n-1)^2,n+1) mod 2], with n>=1 - Paolo P. Lava (paoloplava(AT)gmail.com), Feb 01 2008
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EXAMPLE
| a(7)=6 because [7+5]/2=6
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MATHEMATICA
| a={1}; k=1; For[n=1, n<70, n++, If[EvenQ[k], k=k+8, k=k+5]; k=k/2; AppendTo[a, k]]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), May 26 2007
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CROSSREFS
| Cf. A081742 A089610 A014499 A071673.
Sequence in context: A070737 A135599 A167161 * A181590 A078923 A165240
Adjacent sequences: A128997 A128998 A128999 * A129001 A129002 A129003
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KEYWORD
| easy,nonn
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AUTHOR
| Adam F. Schwartz (adam_s(AT)mit.edu), May 01 2007
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EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), May 26 2007
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