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A136312
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Cubes that are the sum of 2 or more consecutive positive squares.
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1
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103823, 274625, 781229961, 10091699281, 22425768000, 1853614522304, 2277044900416, 4708686519081, 6168761704000, 82312875000000, 235125028708361, 259266910222125, 269648738245125, 291658484677013, 980893000925279, 1568173521032000
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..16.
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EXAMPLE
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103823 is the sum of 47 consecutive squares from 22^2 to 68^2. 82312875000000 is the sum of 10368 consecutive squares from 83868^2 to 94235^2.
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PROG
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(PARI) find(lim)=my(t, v=List()); for(k=2, (3*lim)^(1/3), t=k*(k-1)*(2*k-1)/6; for(n=k, (k-1)/2+sqrt(lim/k-(k^2-1)/12), if(ispower(t+=n^2-(n-k)^2, 3), listput(v, t)))); vecsort(Vec(v), , 8) \\ Charles R Greathouse IV, Jun 11 2011
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CROSSREFS
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Cf. A131643, A000578, A000290.
Sequence in context: A147526 A171162 A210180 * A205260 A076761 A129241
Adjacent sequences: A136309 A136310 A136311 * A136313 A136314 A136315
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KEYWORD
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nonn,changed
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AUTHOR
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Donovan Johnson, Mar 23 2008
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EXTENSIONS
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Edited definition and a(11)-a(14) from Donovan Johnson, Oct 01 2010
a(15)-a(16) from Donovan Johnson, Jun 11 2011
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STATUS
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approved
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