login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A153158 A007916(n)^2. 6
4, 9, 25, 36, 49, 100, 121, 144, 169, 196, 225, 289, 324, 361, 400, 441, 484, 529, 576, 676, 784, 841, 900, 961, 1089, 1156, 1225, 1369, 1444, 1521, 1600, 1681, 1764, 1849, 1936, 2025, 2116, 2209, 2304, 2500, 2601, 2704, 2809, 2916, 3025, 3136, 3249, 3364 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

2^2=4, 3^2=9, 4^2=16=2^4 is not in the sequence, 5^2=25, 6^2=36, ...

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

FORMULA

GCD(exponents in prime factorization of a(n)) = 2, cf. A124010. [Reinhard Zumkeller, Apr 13 2012]

MATHEMATICA

Select[Range[2, 100], GCD@@Last/@FactorInteger@#==1&]^2

PROG

(Haskell)

a153158 n = a153158_list !! (n-1)

a153158_list = filter ((== 2) . foldl1 gcd . a124010_row) [2..]

-- Reinhard Zumkeller, Apr 13 2012

CROSSREFS

Cf. A007916, A153147, A153157, A153159, A153160, A062503.

Sequence in context: A182120 A099998 A030140 * A111245 A062503 A248648

Adjacent sequences:  A153155 A153156 A153157 * A153159 A153160 A153161

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Dec 19 2008

EXTENSIONS

Edited by Ray Chandler, Dec 22 2008

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 21 14:40 EST 2018. Contains 299414 sequences. (Running on oeis4.)