A102216 2-Suzanne numbers.

4, 8, 15, 22, 26, 35, 42, 44, 60, 62, 64, 68, 84, 88, 99, 118, 121, 123, 129, 136, 138, 141, 143, 145, 152, 158, 161, 165, 169, 174, 176, 183, 187, 189, 194, 196, 198, 200, 202, 206, 208, 215, 231, 235, 240, 242, 246, 248, 255, 273, 275, 279, 280, 282, 284

Offset: 1

Author

Eric W. Weisstein, Dec 30 2004

Keywords

• nonn
• base

Comments

From Amiram Eldar, Apr 23 2021: (Start)

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.

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

References

• József Sándor and Borislav Crstici, Handbook of Number theory II, Kluwer Academic Publishers, 2004, Chapter 4, p. 384.
• James J. Tattersall, Elementary Number Theory in Nine Chapters, 2nd ed., Cambridge University Press, 2005, p. 93.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Michael Smith, Cousins of Smith Numbers: Monica and Suzanne Sets, Fibonacci Quarterly, Vol. 34, No. 2 (1996), pp. 102-104.
• Eric Weisstein's World of Mathematics, Suzanne Set.

Crossrefs

Subsequence of A102218.

Cf. A007953, A018252, A102217, A118503.

Programs

Mathematica

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 *)