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A110013
Squares of the form 4p + 5, where p is a prime.
5
25, 49, 81, 121, 169, 289, 361, 441, 529, 729, 961, 1089, 1521, 1681, 1849, 2401, 2809, 3249, 3721, 3969, 5041, 5929, 6241, 6889, 7921, 8281, 8649, 9409, 10201, 11449, 11881, 12321, 12769, 14161, 14641, 16641, 17161, 17689, 18769, 19881, 23409
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OFFSET
1,1
COMMENTS
The sequence contain all squares of greater of twin primes.
LINKS
Amiram Eldar,
Table of n, a(n) for n = 1..10000
FORMULA
a(n) = 4*
A002327
(n) + 5 =
A088502
(n)^2.
MATHEMATICA
Select[4#+5&/@Prime[Range[900]], IntegerQ[Sqrt[#]]&] (*
Harvey P. Dale
, Jan 29 2011 *)
CROSSREFS
Cf.
A002327
,
A002328
,
A088502
.
Cf.
A108604
.
Sequence in context:
A324871
A241836
A110484
*
A374289
A109861
A348754
Adjacent sequences:
A110010
A110011
A110012
*
A110014
A110015
A110016
KEYWORD
easy
,
nonn
AUTHOR
Giovanni Teofilatto
, Sep 03 2005
EXTENSIONS
Corrected and extended by
Ray Chandler
, Sep 04 2005
STATUS
approved