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%I #13 Jan 09 2021 13:29:01
%S 3,12,14,45,61,118,122,124,137,143,152,213,224,225,242,273,277,356,
%T 373,390,392,398,421,428,455,457,460,462,464,510,526,537,560,590,607,
%U 621,673,680,692,746,782,797,804,818,820,866,878,922,939,944,965,980,985
%N Maris-McGwire numbers(2): numbers k such that f(k) = f(k+1), where f(k) = sum of digits of k + sum of digits of the distinct prime factors of k.
%H Amiram Eldar, <a href="/A039945/b039945.txt">Table of n, a(n) for n = 1..10000</a>
%t ds[n_] := Plus @@ IntegerDigits[n]; f[n_] := ds[n] + Total[ds /@ FactorInteger[n][[;; , 1]]]; s = {}; f1 = 1; Do[f2 = f[n]; If[f1 == f2, AppendTo[s, n-1]]; f1 = f2, {n, 2, 1000}]; s (* _Amiram Eldar_, Nov 24 2019 *)
%t SequencePosition[Flatten[Table[Total[IntegerDigits[n]]+Total[Flatten[IntegerDigits/@FactorInteger[n][[All,1]]]],{n,1000}]],{x_,x_}][[All,1]](* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 09 2021 *)
%Y Cf. A045759.
%K nonn,base
%O 1,1
%A _David W. Wilson_
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