|
Search: id:A005735
|
|
|
| A005735 |
|
Greatest k such that binomial(k,n) has fewer than n distinct prime factors.
(Formerly M2719)
|
|
+0
3
|
|
| 1, 3, 8, 14, 32, 62, 87, 169, 132, 367, 389, 510, 394, 512, 512, 1880, 1880, 1882, 2099, 1879, 1885, 2102, 3470, 3470, 4805, 4806, 4806, 3475, 4806, 4938, 4939, 5108, 5119, 6271, 5122, 5869, 10663, 10663, 10663, 7421, 10667, 10667, 10668, 11710, 11711
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Table 2 in Selmer's paper has a typo for n = 76. Selmer "cheats" to find a(n) for n>27. - T. D. Noe (noe(AT)sspectra.com), Apr 05 2007
|
|
REFERENCES
|
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Selmer, Ernst S.; On the number of prime divisors of a binomial coefficient. Math. Scand. 39 (1976), no. 2, 271-281.
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..500
Selmer, Ernst S.; On the number of prime divisors of a binomial coefficient. Math. Scand. 39 (1976), no. 2, 271-281.
|
|
MATHEMATICA
|
Join[{1}, Table[n=k; b=1; n0=Infinity; While[n++; b=b*n/(n-k); If[Length[FactorInteger[b]]<k, n0=n]; n<10*n0]; n0, {k, 2, 30}]] - T. D. Noe (noe(AT)sspectra.com), Apr 05 2007
|
|
CROSSREFS
|
Cf. A005733, A129233.
Sequence in context: A055335 A123329 A129067 this_sequence A135872 A045263 A004733
Adjacent sequences: A005732 A005733 A005734 this_sequence A005736 A005737 A005738
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
EXTENSIONS
|
More terms from Pab Ter (pabrlos(AT)yahoo.com), May 26 2004
Edited by T. D. Noe (noe(AT)sspectra.com), Apr 05 2007
|
|
|
Search completed in 0.002 seconds
|
