21425

Appears in sequences

• Expansion of sum ( q^n / product( 1-q^k, k=1..3*n), n=0..inf ).at n=32A035295
• A self-"read and extend" sequence built following the rules visible in the Comments section (a kind of Collatz-by-digits sequence).at n=21A316764
• Number of dominating sets in the n-double cone graph.at n=6A365581
• Number of mutual-visibility sets in the n-prism graph.at n=10A389184