[go: up one dir, main page]

login
A075055
Smallest integer of the form product (n+1)(n+2)...(n+k)/n!.
3
1, 6, 20, 70, 252, 7, 3432, 12870, 48620, 184756, 705432, 2704156, 10400600, 40116600, 178296, 601080390, 2333606220, 9075135300, 35345263800, 137846528820, 538257874440, 2104098963720, 8233430727600, 32247603683100
OFFSET
1,2
COMMENTS
Differs from A000984 at positions in A058008.
EXAMPLE
a(6) = 7 = 7*8*9*10/6! = 5040/720.
MATHEMATICA
a[n_] := Catch[ For[ k = n-2, True, k++, If[ IntegerQ[an = (n+k)!/n!^2], Throw[an]]]]; a[1]=1; Table[a[n], {n, 1, 24}] (* Jean-François Alcover, Jun 28 2012 *)
CROSSREFS
Cf. A075054.
Sequence in context: A264307 A050930 A074353 * A146891 A235367 A189604
KEYWORD
nice,nonn
AUTHOR
Amarnath Murthy, Sep 07 2002
EXTENSIONS
More terms from Sascha Kurz, Feb 02 2003
STATUS
approved