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A106562
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Perfect squares which are not the sum of two primes.
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12
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1, 121, 289, 529, 625, 961, 1521, 1681, 2025, 2601, 2809, 3249, 3481, 4225, 4489, 5329, 6241, 6561, 6889, 7225, 7569, 8281, 9025, 9409, 9801, 10201, 11025, 11881, 12321, 12769, 13225, 15129, 15625, 16641, 17689, 18769, 19881, 20449, 21609
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(2)=121 because it is the second perfect square which is impossible to obtain summing two primes.
100 is not in the sequence because 100=97+3 (sum of two primes).
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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