639210

Appears in sequences

• Expansion of 1/((1-x)(1-2x)(1-4x)(1-5x)).at n=7A021074
• Group the composite numbers so that the sum of the n-th group is a multiple of the n-th prime: (4), (6), (8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22), (24, 25), (26, 27, 28, 30, 32), (33, 34, ...), ... Sequence gives sum of n-th group.at n=34A074124
• Number of achiral color patterns (set partitions) for a row or loop of length n using exactly 5 colors (sets).at n=19A304975