a(n) is the smallest positive integer such that n*a(n) contains n+a(n) as a substring. If no such number exists then a(n) = -1.
A339144
a(n) is the smallest positive integer such that n*a(n) contains n+a(n) as a substring. If no such number exists then a(n) = -1.
Terms
- a(0) =-1a(1) =2a(2) =-1a(3) =68a(4) =-1a(5) =-1a(6) =-1a(7) =44a(8) =-1a(9) =890a(10) =110a(11) =60a(12) =44a(13) =35a(14) =30a(15) =27a(16) =25a(17) =23a(18) =22a(19) =20a(20) =929a(21) =19a(22) =18a(23) =88a(24) =17a(25) =-1a(26) =16a(27) =16a(28) =68a(29) =15
External references
- oeis: A339144