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Numbers that are the sum of one or more consecutive squares in more than one way.
8

%I #34 Apr 01 2020 01:38:56

%S 25,365,841,1405,1730,2030,3281,3655,3740,4510,4705,4760,4900,5244,

%T 5434,5915,5929,7230,7574,8415,8464,9385,11055,11236,11900,12325,

%U 12524,14905,16745,17484,18879,19005,19044,19855,20449,20510,21790,22806,23681

%N Numbers that are the sum of one or more consecutive squares in more than one way.

%H Paul Richards and David W. Wilson, <a href="/A130052/b130052.txt">Table of n, a(n) for n = 1..10000</a> (first 135 terms from Paul Richards)

%e 25 = 3^2 + 4^2 = 5^2.

%e 365 = 10^2 + 11^2 + 12^2 = 13^2 + 14^2.

%o (PARI) ok(n) = {my(i=sqrtint(n), m=0); while(i>0&&m<2, my(a=i^2, j=i); while(j>0&&a<=n, if(a==n, m+=1); j-=1; a=a+j^2); i-=1); return(m>1)}

%o {for(p=1, 24000, if(ok(p), print1(p,", ")))} \\ _Antonio Roldán_, Mar 09 2020

%Y Cf. A059255 (subsequence).

%K nonn

%O 1,1

%A _Paul Richards_, May 03 2007

%E Extended by _Ray Chandler_, May 04 2007