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A339883
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Values of Euler's totient phi for A050498.
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2
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24, 72, 25440, 33840, 38880, 48960, 99360, 123120, 208320, 458640, 510720, 519360, 532800, 583440, 596400, 622080, 663840, 838800, 846960, 873600, 893760, 942480, 1050480, 1065600, 1078800, 1163040, 1201200, 1327200, 1408320, 1419840, 1567440, 1734000, 1809600
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OFFSET
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1,1
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COMMENTS
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For the shown values the arithmetic progression with difference 6 has exactly 4 terms. Conjecture 1: this holds for all A050498 entries.
Conjecture 2: All a(n) are divisible by 24, starting with [1, 3, 1060, 1410, 1620, 2040, 4140, 5130, 8680, 19110, 21280, 21640, 22200, 24310, 24850, 25920, 27660, 34950, 35290, 36400, 37240, 39270, 43770, 44400, 44950, 48460, ...].
In the Lal and Gillard link only the first three A050498 values (with n <= 10^5) and their corresponding phi values are given.
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REFERENCES
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David Wells, Curious and interesting numbers, Penguin Books, Revised edition, 1997 p. 112. [Gives under the number 72 the first three values of A050498 but with 76236 instead of 76326]
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LINKS
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FORMULA
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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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