

A194041


Lucky numbers which are also unhappy numbers.


1



3, 9, 15, 21, 25, 33, 37, 43, 51, 63, 67, 69, 73, 75, 87, 93, 99, 105, 111, 115, 127, 135, 141, 151, 159, 163, 169, 171, 189, 195, 201, 205, 211, 223, 231, 235, 237, 241, 259, 261, 267, 273, 283, 285, 289, 297, 303, 307, 321, 327, 339, 349, 357, 361, 385, 393
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OFFSET

1,1


COMMENTS

An unhappy number is a number that is not happy (A007770) i.e., a number n such that iterating this sumofsquareddigits map starting with n never reaches the number 1. Many asymptotic properties of the prime numbers are shared by the lucky numbers.


LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..1000
Eric W. Weisstein, Unhappy Number
Eric W. Weisstein, Lucky Number


FORMULA

A000959 INTERSECTION A031177. {k such that k is in A000959 and k is not in A007770}.


CROSSREFS

Cf. A000959, A007770, A031177.
Sequence in context: A307202 A162488 A324298 * A029506 A299790 A030594
Adjacent sequences: A194038 A194039 A194040 * A194042 A194043 A194044


KEYWORD

nonn,easy


AUTHOR

Jonathan Vos Post, Aug 12 2011


STATUS

approved



