login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A063734 Square abundant numbers. 1

%I #14 Jun 25 2018 22:57:53

%S 36,100,144,196,324,400,576,784,900,1296,1600,1764,1936,2304,2500,

%T 2704,2916,3136,3600,4356,4624,4900,5184,5776,6084,6400,7056,7744,

%U 8100,8464,9216,9604,10000,10404,10816,11025,11664,12100,12544,12996,13456,14400

%N Square abundant numbers.

%H Harry J. Smith, <a href="/A063734/b063734.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[150]^2,DivisorSigma[1,#]>2#&] (* _Harvey P. Dale_, Aug 14 2014 *)

%o (PARI) j=[]; for(n=1,25000, if(sigma(n)>(2*n),a=n; if(issquare(a),j=concat(j,a)))); j

%o (PARI) { n=0; for (m=1, 10^9, if (issquare(m) && sigma(m)>(2*m), write("b063734.txt", n++, " ", m); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 29 2009

%o (PARI) { n=0; for (m=1, 10^9, s=m^2; if (sigma(s)>(2*s), write("b063734.txt", n++, " ", s); if (n==1000, break)) ) } \\ _Harry J. Smith_, Aug 29 2009

%Y Cf. A005101.

%K nonn

%O 1,1

%A _Jason Earls_, Aug 13 2001

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 23:26 EDT 2024. Contains 371917 sequences. (Running on oeis4.)