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A062791
Moebius transform of central binomial coefficients.
1
1, 1, 2, 4, 9, 16, 34, 64, 123, 241, 461, 900, 1715, 3396, 6423, 12800, 24309, 48477, 92377, 184500, 352679, 704969, 1352077, 2703168, 5200290, 10398883, 20058174, 40113164, 77558759, 155110827, 300540194, 601067520, 1166802646, 2333581909, 4537567606
OFFSET
1,3
LINKS
FORMULA
a(n) = Sum_{d|n} A001405(n/d)*mu(d).
EXAMPLE
n=7, C[7,3]=35, A001405[7/d]={C[7,3],C[1,0]}={35,1}, mu[d]={1,-1}, the sum is a(7)=35-1=34.
MAPLE
with(numtheory):
a:= n-> add(binomial(d, iquo(d, 2))*mobius(n/d), d=divisors(n)):
seq(a(n), n=1..40); # Alois P. Heinz, Jul 09 2017
CROSSREFS
Cf. A001405.
Sequence in context: A302831 A091437 A131337 * A203320 A005980 A128093
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 19 2001
EXTENSIONS
Offset corrected by Eric Rowland, Jul 09 2017
STATUS
approved