5432161
domain: N
Appears in sequences
- Triangle read by rows: T(n,k) = (1/k) times the number of functions from an n-element set into but not onto a k-element set.at n=42A101031
- a(n) is the number of nonnegative integers k less than 10^n such that the decimal representation of k lacks digits 1,2,3 and at least one of digits 4,5,6,7,8,9.at n=7A126627