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Integers which can be written as a sum of at least 2 consecutive squares in at least 3 different ways.
5

%I #24 May 25 2019 01:56:28

%S 147441,910805,1026745,2403800,2513434,3198550,11739805,15053585,

%T 18646301,33313175,93812510,102939515,134910295,136448235,151443110,

%U 163998695,195435485,197780465,213872920,267043455,461498779,482204660,554503705,559990541,601704095

%N Integers which can be written as a sum of at least 2 consecutive squares in at least 3 different ways.

%C The smallest number which can be expressed in 4 such ways is 554503705, which is equal to the sum of squares of the integers in the closed intervals (480,1210), (3570,3612), (3613,3654) and (7442,7451). - _Giovanni Resta_, Jul 25 2007

%H David W. Wilson, <a href="/A111044/b111044.txt">Table of n, a(n) for n = 1..754</a>

%H Sebastien DUMORTIER, <a href="http://les-mathematiques.u-strasbg.fr/phorum/read.php?f=2&amp;i=208903&amp;t=208903">Perfect Numbers</a> [Broken link?]

%e 147441 = 85^2 + 86^2 + ... + 101^2 = 29^2 + 30^2 + ... + 77^2 = 18^2 + 19^2 + ... + 76^2;

%e 910805 = 550^2 + 551^2 + 552^2 = 144^2 + 145^2 + ... + 178^2 = 35^2 + 36^2 + ... + 140^2;

%e 1026745 = 716^2 + 717^2 = 51^2 + 52^2 + ... + 147^2 = 1^2 + 2^2 + ... + 145^2;

%e 2403800 = 583^2 + 584^2 + ... + 589^2 = 368^2 + 369^2 + ... + 384^2 = 298^2 + 299^2 + ... + 322^2;

%e 2513434 = 473^2 + 474^2 + ... + 483^2 = 286^2 + 287^2 + ... + 313^2 = 66^2 + 67^2 + ... + 198^2;

%e 3198550 = 225^2 + 226^2 + ... + 275^2 = 127^2 + 128^2 + ... + 226^2 = 1^2 + 2^2 + ... + 212^2.

%Y See also: A001653, A097812, A062681, A174069.

%K nonn

%O 1,1

%A _Sébastien Dumortier_, Oct 06 2005

%E More terms from _Giovanni Resta_, Jul 25 2007