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A048197 Numbers n for which binomial [ n, Floor [ n/2 ] ] has more unitary than non-unitary divisors. 0
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 15, 16, 17, 18, 19, 20, 21, 23, 24, 31, 32, 35, 39, 41, 43, 55 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A048107 is applied to central binomial coefficients. This sequence includes the 12 known squarefree central binomial coefficients i.e. 1,2,3,4,5,7,8,11,17,19,23,71 collected in A046098

FORMULA

A034444[ A001405[ n ] ] > A048105[ A001405[ n ] ]

EXAMPLE

n=59 when the corresponding binomial[ 59,29 ] has 8192 divisors, of which 4096 are unitary and equally 4096 are not such ones.

CROSSREFS

A001405, A034444, A048107, A046098.

Sequence in context: A030700 A105208 A074779 * A193671 A073491 A066311

Adjacent sequences:  A048194 A048195 A048196 * A048198 A048199 A048200

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu)

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.