A111948 - OEIS

A111948

Admirable Harshad numbers n such that the subtracted divisor is equal to the digital sum of n.

24, 42, 114, 222, 402, 2022, 2202, 7588, 8596, 10014, 11202, 12102, 17668, 21102, 27748, 29764, 31002, 32788, 39844, 42868, 43876, 45388, 46396, 48916, 49924, 55972, 56476, 57484, 58492, 65548, 66556, 69076, 70588, 71596, 78148, 81676

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OFFSET

1,1

LINKS

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

EXAMPLE

a(2)=42 because 1+2+3+7+14+21-6 = 42 and 42/6 = 7.

MATHEMATICA

harsQ[n_] := Divisible[n, Plus @@ IntegerDigits[n]]; admQ[n_] := (ab = DivisorSigma[1, n] - 2 n) > 0 && EvenQ[ab] && Plus @@ IntegerDigits[n] == ab/2 && ab/2 < n && Divisible[n, ab/2]; Select[Range[100000], harsQ[#] && admQ[#] &] (* Amiram Eldar, Oct 27 2019 *)

CROSSREFS

Cf. A111592, A005349, A111947.

Sequence in context: A074975 A077095 A228844 * A039411 A043234 A044014

Adjacent sequences: A111945 A111946 A111947 * A111949 A111950 A111951

KEYWORD

base,nonn

AUTHOR

Jason Earls, Aug 22 2005

STATUS

approved