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A111948 Admirable Harshad numbers n such that the subtracted divisor is equal to the digital sum of n. 3
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified April 13 01:36 EDT 2021. Contains 342934 sequences. (Running on oeis4.)