Undulating Harshad numbers: numbers divisible by the sum of their own digits with decimal expansions in an abab...ab pattern.

A129120

Undulating Harshad numbers: numbers divisible by the sum of their own digits with decimal expansions in an abab...ab pattern.

Terms

    a(0) =10a(1) =12a(2) =18a(3) =20a(4) =21a(5) =24a(6) =27a(7) =30a(8) =36a(9) =40a(10) =42a(11) =45a(12) =48a(13) =50a(14) =54a(15) =60a(16) =63a(17) =70a(18) =72a(19) =80a(20) =81a(21) =84a(22) =90a(23) =171a(24) =252a(25) =414a(26) =828a(27) =1010a(28) =1212a(29) =1818

External references