147147

Appears in sequences

• Lucky numbers that are concatenations of a number k with itself.at n=19A032650
• G.f. A(x) satisfies: A( x*A(x) - x*A(x)^3 ) = x^2.at n=9A292078
• After a(1) = 1, the sequence is always extended with the smallest divisor d (not yet present in the sequence) of the last term t. If d doesn't exist, we extend the sequence with tt (t concatenated to itself). If tt doesn't produce a new d, we extend the sequence with ttt, etc. See the Comments section for more details.at n=40A348871
• Irregular triangle read by rows: T(r,c) is the product of the number of standard Young tableaux (A117506) and the number of semistandard Young tableaux (A262030) for partitions of r.at n=46A380611