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PROJECT EULER · #0261

Pivotal Square Sums

Statement only · SolvedOriginal problem ↗

Let us call a positive integer k a square-pivot, if there is a pair of integers m>0 and nk, such that the sum of the (m+1) consecutive squares up to k equals the sum of the m consecutive squares from (n+1) on:

(km)2++k2=(n+1)2++(n+m)2.

Some small square-pivots are

  • 4: 32+42=52
  • 21: 202+212=292
  • 24: 212+222+232+242=252+262+272
  • 110: 1082+1092+1102=1332+1342

Find the sum of all distinct square-pivots 1010.

Write-up coming later

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