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 A173632 a(n)=sqrt((A173631(n))^2-4*P_n), where P_n is product of first n primes, if this value is integer and a(n)=0, otherwise 0
 0, 1, 1, 1, 1, 13, 17, 1, 41, 157, 0, 0, 0, 0, 17659, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS a(14) appears to be the last nonzero term. LINKS MATHEMATICA p=4; Join[{0}, Table[p=p*Prime[n]; q=Sqrt[Ceiling[Sqrt[p]]^2-p]; If[IntegerQ[q], q, 0], {n, 200}]] CROSSREFS Cf. A173631, A002110, A000040 Sequence in context: A107081 A029526 A219949 * A061060 A084307 A066918 Adjacent sequences: A173629 A173630 A173631 * A173633 A173634 A173635 KEYWORD nonn AUTHOR Vladimir Shevelev, Nov 23 2010 EXTENSIONS Extended by T. D. Noe, Nov 23 2010 STATUS approved

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Last modified March 28 23:19 EDT 2023. Contains 361596 sequences. (Running on oeis4.)