29431

Appears in sequences

• Numerator of Sum_{k=1..n} k/phi(k).at n=21A068885
• Number of partitions of an n-set with exactly one even block.at n=9A096579
• Triangle read by rows: T(n,k) is the number of set partitions of {1,2,...,n} (or of any n-set) having k blocks of even size (0<=k<=floor(n/2)).at n=31A124322
• Number of n X 3 binary arrays with top left value 1 and no two ones adjacent horizontally, vertically or nw-se diagonally.at n=9A228278
• Numbers m for which there exists a k>=2 such that m equals the average of digitsum(m^p) for p from 1 to k.at n=28A259313
• a(n) = numerator of Sum_{d|n} tau(d)/pod(d) where tau(k) = the number of the divisors of k (A000005) and pod(k) = the product of the divisors of k (A007955).at n=27A323706
• Centered pentagonal numbers which are squarefree semiprimes.at n=38A381043
• Centered pentagonal numbers which are semiprimes.at n=39A382132