For every positive integer m, let u(m) = (d(1),d(2),...,d(k)) be the unitary divisors of m. The sequence (a(n)) consists of successive numbers m which d(k)/d(1) + d(k-1)/d(2) + ... + d(k)/d(1) is an integer.

A229996

For every positive integer m, let u(m) = (d(1),d(2),...,d(k)) be the unitary divisors of m. The sequence (a(n)) consists of successive numbers m which d(k)/d(1) + d(k-1)/d(2) + ... + d(k)/d(1) is an integer.

Terms

    a(0) =1a(1) =10a(2) =65a(3) =130a(4) =260a(5) =340a(6) =1105a(7) =1972a(8) =2210a(9) =4420a(10) =8840a(11) =9860a(12) =15650a(13) =20737a(14) =32045a(15) =41474a(16) =44200a(17) =51272a(18) =55250a(19) =64090a(20) =75140a(21) =82948a(22) =103685a(23) =128180a(24) =207370a(25) =207553a(26) =221000a(27) =256360a(28) =352529a(29) =414740

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