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2-Suzanne numbers.
11

%I #12 Apr 23 2021 05:17:44

%S 4,8,15,22,26,35,42,44,60,62,64,68,84,88,99,118,121,123,129,136,138,

%T 141,143,145,152,158,161,165,169,174,176,183,187,189,194,196,198,200,

%U 202,206,208,215,231,235,240,242,246,248,255,273,275,279,280,282,284

%N 2-Suzanne numbers.

%C From _Amiram Eldar_, Apr 23 2021: (Start)

%C Composite numbers k such that the sum of digits of k (A007953) and the sum of sums of digits of the prime factors of k (taken with multiplicity, A118503) are both even.

%C The Monica and Suzanne sets were named by Smith (1996) after his two cousins, Monica and Suzanne Hammer. (End)

%D József Sándor and Borislav Crstici, Handbook of Number theory II, Kluwer Academic Publishers, 2004, Chapter 4, p. 384.

%D James J. Tattersall, Elementary Number Theory in Nine Chapters, 2nd ed., Cambridge University Press, 2005, p. 93.

%H Amiram Eldar, <a href="/A102216/b102216.txt">Table of n, a(n) for n = 1..10000</a>

%H Michael Smith, <a href="https://www.fq.math.ca/Scanned/34-2/smith.pdf">Cousins of Smith Numbers: Monica and Suzanne Sets</a>, Fibonacci Quarterly, Vol. 34, No. 2 (1996), pp. 102-104.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SuzanneSet.html">Suzanne Set</a>.

%t s[n_] := Plus @@ IntegerDigits[n]; f[p_, e_] := e*s[p]; sp[n_] := Plus @@ f @@@ FactorInteger[n]; suz2Q[n_] := CompositeQ[n] && And @@ EvenQ[{s[n], sp[n]}]; Select[Range[300], suz2Q] (* _Amiram Eldar_, Apr 23 2021 *)

%Y Subsequence of A102218.

%Y Cf. A007953, A018252, A102217, A118503.

%K nonn,base

%O 1,1

%A _Eric W. Weisstein_, Dec 30 2004