|
| |
|
|
A037239
|
|
Numerator of Pi^(2n)/(GAMMA(2n)*(1-2^(-2n))*Zeta(2n)); = 8*(highest power of 2 dividing n).
|
|
1
| |
|
|
8, 16, 8, 32, 8, 16, 8, 64, 8, 16, 8, 32, 8, 16, 8, 128, 8, 16, 8, 32, 8, 16, 8, 64, 8, 16, 8, 32, 8, 16, 8, 256, 8, 16, 8, 32, 8, 16, 8, 64, 8, 16, 8, 32, 8, 16, 8, 128, 8, 16, 8, 32, 8, 16, 8, 64, 8, 16, 8, 32, 8, 16, 8, 512, 8, 16, 8, 32, 8, 16, 8, 64, 8
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
REFERENCES
| H. Cohn, Bull. Am. Math. Soc., Sept. 1965, 681ff, esp. p. 688.
|
|
|
MAPLE
| with(numtheory): for n from 1 to 200 do if n mod 2 = 1 then printf(`%d, `, 8) else printf(`%d, `, 8*2^ifactors(n)[2][1][2]) fi; od:
|
|
|
MATHEMATICA
| a[n_] := 8*BitAnd[n, -n]; Table[a[n], {n, 1, 81}] (* From Jean-François Alcover, Sep 20 2011, after Joerg Arndt *)
|
|
|
PROG
| (PARI) a(n)=if(n<1, 0, 8*2^valuation(n, 2))
|
|
|
CROSSREFS
| Equals 8*A006519. Denominators given by A002425.
Sequence in context: A073925 A053321 A174256 * A205869 A103699 A040056
Adjacent sequences: A037236 A037237 A037238 * A037240 A037241 A037242
|
|
|
KEYWORD
| nonn,frac,easy
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| More terms from James A. Sellers (sellersj(AT)math.psu.edu), Jun 20 2000
|
| |
|
|
