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A166255
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Numbers n with property that sum of 70 successive primes starting with n-th prime is a square.
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1
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71, 201, 1024, 1594, 10915, 36934, 51050, 60054, 60914, 71822, 80331, 85230, 92916, 96352, 103271, 114667, 151019, 158591, 183484, 184348, 193979, 196078, 223587, 277476, 295890, 309502, 317601, 334181, 338139, 369101, 485330, 494188, 530832
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OFFSET
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1,1
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COMMENTS
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Sum(prime(k),k=n,n+69)=s^2; corresponding values of s: 200, 322, 770, 982, 2848, 5552, 6622, 7236, 7292, 7972, 8472, 8750, 9166 (A166256).
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LINKS
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Table of n, a(n) for n=1..33.
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EXAMPLE
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prime(71)+...+prime(71+69)=200^2=A166256(1)^2,
prime(201)+...+prime(201+69)=322^2=A166256(2)^2,
prime(1024)+...+prime(1024+69)=770^2=A166256(3)^2.
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MATHEMATICA
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PrimePi[First[#]]&/@Select[Partition[Prime[Range[1000000]], 70, 1], IntegerQ[ Sqrt[ Total[#]]]&] (* From Harvey P. Dale, June 13 2011 *)
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CROSSREFS
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Cf. A166256.
Sequence in context: A142808 A101110 A142893 * A142076 A096698 A159472
Adjacent sequences: A166252 A166253 A166254 * A166256 A166257 A166258
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KEYWORD
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nonn
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AUTHOR
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Zak Seidov, Oct 10 2009
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STATUS
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approved
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