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 A118912 a(1) = 2; a(n) is greatest prime < a(n-1)^4. 1
 2, 13, 28559, 665230244078823349, 195833931687186822327230545227550596864953022841534058316595001440791433 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Exponent-4 analog of A059785 a(n+1)=prevprime(a(n)^2), with exponent 3 being A118910 a(1) = 2; a(n) is greatest prime < a(n-1)^3. LINKS FORMULA a(1) = 2; a(n) is greatest prime < a(n-1)^4. EXAMPLE a(1) = 2, by definition. a(2) = 13 = 2^4 - 3. a(3) = 28559 = 13^4 - 2. a(4) = 665230244078823349 = 28559^4 - 12. a(5) = 195833931687186822327230545227550596864953022841534058316595001440791433 = 665230244078823349^4 - 168. a(6) is too large to include. CROSSREFS Cf. A001358, A055496, A076656, A006992, A005384, A005385, A118908-A118913. Sequence in context: A111016 A176947 A280798 * A027680 A241569 A262299 Adjacent sequences:  A118909 A118910 A118911 * A118913 A118914 A118915 KEYWORD easy,nonn AUTHOR Jonathan Vos Post, May 05 2006 STATUS approved

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Last modified May 30 08:43 EDT 2020. Contains 334712 sequences. (Running on oeis4.)