10000128domain: NAppears in sequencesSmallest n-digit number divisible by 2^n.at n=7A050621a(n) = Sum_{0<d|n, n/d odd} d^7.at n=9A096961a(n) = Sum_{d|n, n/d==1 mod 4} d^7 - Sum_{d|n, n/d==3 mod 4} d^7.at n=9A321831Sum of the 7th powers of the divisor complements of the odd proper divisors of n.at n=9A352053