The congruence speed formula
2021 ◽
Vol 27
(4)
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pp. 43-61
We solve a few open problems related to a peculiar property of the integer tetration ^{b}a, which is the constancy of its congruence speed for any sufficiently large b = b(a). Assuming radix-10 (the well known decimal numeral system), we provide an explicit formula for the congruence speed V(a) ∈ ℕ_0 of any a ∈ ℕ − {0} that is not a multiple of 10. In particular, for any given n ∈ ℕ, we prove to be true Ripà’s conjecture on the smallest a such that V(a) = n. Moreover, for any a ≠ 1 ∶ a ≢ 0 (mod 10), we show the existence of infinitely many prime numbers, p_j = p_j(V(a)), such that V(p_j) = V(a).
2010 ◽
Vol 53
(3)
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pp. 791-812
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2019 ◽
Vol 19
(06)
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pp. 2050101
2020 ◽
Vol DMTCS Proceedings, 28th...
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Keyword(s):
2004 ◽
Vol 41
(3)
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pp. 309-324
Keyword(s):
2008 ◽
Vol 4
(3)
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pp. 181-192
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Keyword(s):
Keyword(s):