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A059935
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Fourth step in Goodstein sequences, i.e., g(6) if g(2)=n: write g(5)=A059934(n) in hereditary representation base 5, bump to base 6, then subtract 1 to produce g(6).
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16
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1, 83, 775, 46655, 46657, 93395, 140743, 279935, 279937, 280019, 280711, 326591, 326593, 19916489515870532960258562190639398471599239042185934648024761145811
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OFFSET
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3,2
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COMMENTS
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2.659...*10^36305 = a(18) < a(19) < ... < a(31) = a(18) + 326594. - Pontus von Brömssen, Sep 20 2020
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LINKS
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EXAMPLE
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a(12) = 280019 since with g(2) = 12 = 2^(2 + 1) + 2^2, we get g(3) = 3^(3 + 1) + 3^3-1 = 107 = 3^(3 + 1) + 2*3^2 + 2*3 + 2, g(4) = 4^(4 + 1) + 2*4^2 + 2*4 + 1 = 1065, g(5) = 5^(5 + 1) + 2*5^2 + 2*5 = 15685 and g(6) = 6^(6 + 1) + 2*6^2 + 6 + 5 = 280019.
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PROG
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(Haskell) see Link
(Python)
from sympy.ntheory.factor_ import digits
def bump(n, b):
s=digits(n, b)[1:]
l=len(s)
return sum(s[i]*(b+1)**bump(l-i-1, b) for i in range(l) if s[i])
for i in range(2, 6):
n=bump(n, i)-1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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