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 A115398 Numbers n such that both n^2+1 and 2^n + 1 are semiprimes. 0
 3, 5, 11, 12, 19, 28, 61, 64, 79, 92, 101, 104, 199, 356, 596, 692 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A085722 and A092559. LINKS EXAMPLE 11 is OK because 11^2+1=122=2*61 (semiprime) and 2^11+1=2049=3*683 (semiprime). CROSSREFS Cf. A085722, A092559. Sequence in context: A006538 A066281 A072063 * A014597 A130603 A069977 Adjacent sequences:  A115395 A115396 A115397 * A115399 A115400 A115401 KEYWORD more,nonn AUTHOR Zak Seidov, Mar 08 2006 STATUS approved

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