|
%I #38 May 04 2020 04:57:35
%S 0,10,102,3012,13240,123540,3516240,16453720,123567480,9123567480
%N a(n) is the smallest n-digit number using each digit 0 to n-1 once, such that the numbers formed by its last k digits are divisible by k, (k = 1..n).
%C a(n) = A147636(n) for n=1, 2, 3, 9 and 10.
%e a(3) = 3012 because 2, 12, 012, 3012 are divisible by 1, 2, 3, 4 and it is the least such number with distinct digits 0 to 3.
%t ok[n_] := AllTrue[Range@ IntegerLength@ n, Mod[ Mod[n, 10^#], #] == 0 &]; a[n_] := SelectFirst[ FromDigits /@ Permutations[Range[0, n-1]], # >= 10^(n-1) - 1 && ok[#] &]; Array[a, 10] (* _Giovanni Resta_, May 04 2020 *)
%Y Cf. A147636, A158242, A220491.
%K base,fini,full,nonn
%O 1,2
%A _Eduardo P. Feitosa_, May 03 2020
|
