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 A211378 Goodstein sequence starting with 19. 28
 19, 7625597484990, 13407807929942597099574024998205846127479365820592393377723561443721764030073546976801874298166903427690031858186486050853753882811946569946433649006084099 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS To calculate a(n), write a(n-1) in the hereditary representation base n+1, then bump the base to n+2, then subtract 1. LINKS Eric Weisstein's World of Mathematics, Goodstein Sequence Wikipedia, Goodstein's Theorem Reinhard Zumkeller, Haskell programs for Goodstein sequences EXAMPLE The first terms are (see Wikipedia): a(0) = 2^2^2 + 2^1 + 2^0 = 19 a(1) = 3^3^3 + 3^1 + 3^0 - 1 = 7625597484990 a(2) = 4^4^4 + 4^1 - 1                       (155 digits) a(3) = 5^5^5 + 3 - 1                         (2185 digits) a(4) = 6^6^6 + 2 - 1                         (36306 digits) a(5) = 7^7^7 + 1 - 1                         (695975 digits) a(6) = 8^8^8 - 1                             (15151336 digits). PROG (Haskell)  see Link CROSSREFS Cf. A215409 (start=3), A056193 (start=4), A222117 (start=15), A059933 (start=16). Sequence in context: A038028 A013890 A128400 * A133591 A137643 A023921 Adjacent sequences:  A211375 A211376 A211377 * A211379 A211380 A211381 KEYWORD nonn,fini AUTHOR Reinhard Zumkeller, Feb 13 2013 EXTENSIONS Offset changed to 0 by Nicholas Matteo, Aug 21 2019 STATUS approved

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Last modified December 15 04:20 EST 2019. Contains 329991 sequences. (Running on oeis4.)