A337171 a(n) = A004186(n) mod n.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, 5, 13, 6, 13, 3, 9, 15, 0, 0, 0, 9, 18, 2, 10, 18, 26, 5, 0, 0, 0, 0, 9, 18, 27, 36, 7, 15, 0, 0, 0, 0, 0, 9, 18, 27, 36, 45, 0, 0, 0, 0, 0, 0, 9, 18, 27, 36, 0, 0, 0, 0, 0, 0, 0, 9, 18, 27, 0, 0, 0, 0, 0, 0, 0, 0, 9, 18

Offset: 1

Author

Simon Strandgaard, Jan 28 2021

Keywords

• nonn
• base

Examples

			a(12) = A004186(12) mod 12 = 21 mod 12 = 9,
a(13) = A004186(13) mod 13 = 31 mod 13 = 5,
a(14) = A004186(14) mod 14 = 41 mod 14 = 13,
a(15) = A004186(15) mod 15 = 51 mod 15 = 6,
a(16) = A004186(16) mod 16 = 61 mod 16 = 13.
		

Links

• Simon Strandgaard, Plot of 1000 terms

Crossrefs

Cf. A004186.

Cf. A319650 (similar in binary).

Programs

Mathematica

a[n_] := Mod[FromDigits @ Sort[IntegerDigits[n], Greater], n]; Array[a, 100] (* Amiram Eldar, Jan 30 2021 *)

PARI

a(n) = fromdigits(vecsort(digits(n), , 4)) % n; \\ Michel Marcus, Mar 04 2021

Ruby

values = (1..20).map do |n|
    n.to_s.split('').sort.join.reverse.to_i % n
end
p values