A111947 Admirable Harshad numbers.

12, 20, 24, 30, 40, 42, 54, 70, 84, 102, 114, 120, 140, 222, 224, 234, 270, 308, 364, 402, 476, 644, 1002, 1148, 1204, 1638, 1652, 2022, 2202, 2212, 3164, 3250, 3472, 4172, 6200, 7588, 8204, 8432, 8596, 9424, 10002, 10014, 10724, 10792, 11202, 11228

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

a(3)=24 because 1+2+3+4+8+12-6 = 24 and 24/6 = 4.

Mathematica

harsQ[n_] := Divisible[n, Plus @@  IntegerDigits[n]]; admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && ab/2 < n && Divisible[n, ab/2]; Select[Range[12000], harsQ[#] && admQ[#] &] (* Amiram Eldar, Oct 27 2019 *)

Crossrefs

Intersection of A005349 and A111592.

Cf. A111948.

Sequence in context: A332956 A204825 A111592 * A109396 A286004 A055598

Adjacent sequences: A111944 A111945 A111946 * A111948 A111949 A111950

Keyword

base,nonn

Author

Jason Earls, Aug 22 2005

Status

approved