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A262141
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The first of nine consecutive positive integers the sum of the squares of which is equal to the sum of the squares of ten consecutive positive integers.
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2
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181, 7021, 266761, 10130041, 384674941, 14607517861, 554701003921, 21064030631281, 799878462984901, 30374317562795101, 1153424188923229081, 43799744861519910121, 1663236880548833355661, 63159201715994147605141, 2398386428327228775639841
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OFFSET
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1,1
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COMMENTS
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For the first of the corresponding ten consecutive positive integers, see A262142.
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LINKS
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FORMULA
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a(n) = 39*a(n-1)-39*a(n-2)+a(n-3) for n>3.
G.f.: -x*(x^2-38*x+181) / ((x-1)*(x^2-38*x+1)).
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EXAMPLE
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181 is in the sequence because 181^2 + ... + 189^2 = 308085 = 171^2 + ... + 180^2.
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PROG
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(PARI) Vec(-x*(x^2-38*x+181)/((x-1)*(x^2-38*x+1)) + O(x^30))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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