A249764 Numbers which divide the concatenation, in ascending order, of their anti-divisors.

15, 30, 105, 120, 150, 222, 375, 585, 1500, 1695, 1755, 1800, 2700, 3449, 3750, 3840, 4891, 6720, 7680, 12000, 13583, 14400, 15000, 18750, 19200, 20940, 28134, 30000, 34800, 35625, 46875, 48000, 68400, 72504, 75000, 93750, 120000, 128400

Offset

1,1

Links

Chai Wah Wu, Table of n, a(n) for n = 1..103

Example

Anti-divisors of 15 are 2, 6, 10 and their concatenation in ascending order is 2610. Finally, 2610 / 15 = 174.

Maple

P:=proc(q) local a, k, n; for n from 3 to q do a:=0;
for k from 2 to n-1 do if abs((n mod k)-k/2)<1 then a:=a*10^(ilog10(k)+1)+k; fi; od;
if type(a/n, integer) then print(n); fi; od; end: P(10^9);

Crossrefs

Cf. A066272, A069872, A224930, A240265.

Sequence in context: A110286 A254859 A127526 * A202522 A054305 A362986

Adjacent sequences: A249761 A249762 A249763 * A249765 A249766 A249767

Keyword

nonn,base

Author

Paolo P. Lava, Nov 05 2014

Status

approved