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A080389 Numbers n such that GCD[A001405(n+1), A001405(n)]=1; i.e. 2 consecutive central binomial coefficients are relatively prime. 1
1, 2, 3, 4, 6, 7, 8, 10, 12, 15, 16, 18, 20, 22, 24, 26, 28, 30, 31, 36, 40, 42, 46, 48, 52, 54, 56, 58, 60, 63, 64, 66, 70, 72, 74, 78, 80, 82, 88, 96, 100, 102, 106, 108, 112, 114, 118, 120, 124, 126, 127, 130, 132, 136, 138, 148, 150, 156, 162, 166, 168, 170, 172, 178 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

MATHEMATICA

t=Table[GCD[Binomial[w+1, Floor[w+1/2]], Binomial[w, Floor[w/2]]], {w, 1, 256}] Flatten[Position[t, 1]]

CROSSREFS

Cf. A001405, A080388.

Sequence in context: A114149 A062974 A065609 * A181062 A091199 A093452

Adjacent sequences:  A080386 A080387 A080388 * A080390 A080391 A080392

KEYWORD

easy,nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Mar 12 2003

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Last modified February 15 17:46 EST 2012. Contains 205835 sequences.