A062271 Denominators in partial products of the twin prime constant.

4, 64, 256, 1024, 16384, 4194304, 452984832, 603979776, 1073741824, 64424509440, 16698832846848, 8906044184985600, 2244323134616371200, 4588393964104581120, 24471434475224432640, 32628579300299243520

Offset

2,1

References

Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 84-94.

G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 5th ed., Oxford Univ. Press, 1979, ch. 22.20

Links

Table of n, a(n) for n=2..17.

Steven R. Finch, Hardy-Littlewood Constants [Broken link]

Steven R. Finch, Hardy-Littlewood Constants [From the Wayback machine]

Formula

a(n)= a(n-1)*(p(n)-1)^2 / gcd( A062270(n), a(n-1)*(p(n)-1)^2 ) for n > 2.

Example

a(4)= 256= 2*2*4*4*6*6 / gcd( 3*1*5*3*7*5, 2*2*4*4*6*6 ).

Crossrefs

A062270 (numerators), A005597 (decimal expansion).

Sequence in context: A016934 A260182 A056229 * A110258 A056982 A381198

Adjacent sequences: A062268 A062269 A062270 * A062272 A062273 A062274

Keyword

easy,nonn,frac

Author

Frank Ellermann, Jun 16 2001

Status

approved