137533

Appears in sequences

• a(n) = floor( n*(n-1)*(n-2)*(n-3)/26 ).at n=45A011936
• Composite numbers k such that if k = a U b (where U denotes concatenation) then a' + b' = k', where a', b' and k' are the arithmetic derivatives of a, b and k.at n=19A239724
• Composite numbers k = concat(MSD(k),x) such that k' = x', where k' is the arithmetic derivative of k.at n=22A293477
• Composite numbers k = concat(MSD(k),x) such that the sum of the aliquot parts of k is equal to the sum of the aliquot parts of x.at n=26A293479