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A243895
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a(n) = prime(n^2-1).
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2
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5, 19, 47, 89, 149, 223, 307, 409, 523, 659, 823, 997, 1187, 1423, 1613, 1877, 2141, 2423, 2731, 3079, 3457, 3797, 4201, 4621, 5039, 5507, 5987, 6473, 6991, 7561, 8147, 8731, 9337, 9929, 10613, 11317, 12043, 12739, 13487, 14323, 15091, 15859, 16741
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OFFSET
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2,1
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COMMENTS
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The prime numbers prime(k-1), prime(k) = A001248 and prime(k+1) = A243896 with k = n^2 are building a triple of successive prime numbers. Remark: prime(n^2-1) is not defined for n=1.
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LINKS
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FORMULA
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EXAMPLE
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n = 3, n^2 = 9, n^2-1 = 8, prime(8) = 19.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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