436653

Appears in sequences

• Group the natural numbers into groups (1),(2),(3),(4),(5,6),(7,8,9),... so that the n-th group contains N(n) terms, where N(n) is the Narayana's cows sequence (A000930). Sequence contains the sum of the terms in the n-th group.at n=18A301877
• a(n) = A000045(n) * A001003(n).at n=8A380048