

A175180


Numbers n such that n^2 + 2 is powerful in the sense of A001694.


1




OFFSET

1,1


COMMENTS

This sequence is infinite (F. Lucas).
The n^2 are a subset of A076445, so 23 terms of the sequence are known from there.  R. J. Mathar, Mar 05 2010
Together with 1, supersequence of A238799.  Arkadiusz Wesolowski, Mar 06 2014


REFERENCES

J.M. De Koninck, Ces nombres qui nous fascinent, Entry 265, pp 71, Ellipses, Paris 2008.


LINKS

Table of n, a(n) for n=1..6.


EXAMPLE

5 is in the sequence because 5^2 + 2 = 1^2 * 3^3 is powerful.
265 is in the sequence because 265^2 + 2 = 51^2*3^3 is powerful.
13775 is in the sequence because 13775^2 + 2 = 2651^2 * 3^3 is powerful.


PROG

(PARI) is(n)=ispowerful(n^2+2) \\ Charles R Greathouse IV, Feb 04 2013


CROSSREFS

Cf. A001694, A238799.
Sequence in context: A079681 A086656 A034602 * A238799 A113257 A180820
Adjacent sequences: A175177 A175178 A175179 * A175181 A175182 A175183


KEYWORD

nonn


AUTHOR

Michel Lagneau, Mar 01 2010


EXTENSIONS

Examples rephrased by R. J. Mathar, Feb 24 2010, Mar 05 2010


STATUS

approved



