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A227480
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Triangular numbers of the form p^2 - 1 where p is a prime.
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0
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OFFSET
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1,1
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LINKS
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EXAMPLE
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139128 is both 527*528/2 and 373^2 - 1 (and 373 is prime).
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MATHEMATICA
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Select[Prime[Range[100000]]^2-1, OddQ[Sqrt[8#+1]]&] (* The program generates the first six terms of the sequence. *) (* Harvey P. Dale, Sep 17 2023 *)
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CROSSREFS
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KEYWORD
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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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