1004640

Appears in sequences

• Let x be the sum of the divisors d_i of k such that d_i | sigma(k). Sequence lists the numbers k for which x^2 = sigma(k).at n=18A284283
• Triangle read by rows. A generalization of unsigned Lah numbers, called L[3,1].at n=51A290596
• Positions of records in A357299: integers m such that the number of divisors whose first digit equals the first digit of m sets a new record.at n=18A355592