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A054754
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Totient(n) and cototient(n) are squares.
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2
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1, 2, 5, 8, 17, 32, 37, 101, 125, 128, 197, 257, 401, 468, 512, 577, 677, 1297, 1417, 1601, 1872, 2048, 2340, 2917, 3125, 3137, 3145, 4100, 4212, 4357, 4913, 5477, 7057, 7488, 8101, 8192, 8837, 9360, 12101, 13457, 14401, 14841, 15377, 15588, 15877
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OFFSET
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1,2
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COMMENTS
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Subset of A039770, overlaps with A002496.
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LINKS
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Donovan Johnson, Table of n, a(n) for n = 1..10000
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FORMULA
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A000010(a(n))=x^2 and a(n)-A000010(a(n))=y^2.
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EXAMPLE
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a(n) is an odd power of a prime q = w^2+1, like 4913 = 17^3, where A000010(a(31)) = phi(4913) = 4624 = 68^2 and A051953(4913) = 4913-4624 = 289 = 17^2. a(n) is not an odd power of a prime of A002496, like a(14) = 468, where phi(468) = 144 and 468-phi(468) = 324 = 18^2.
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CROSSREFS
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Cf. A000010, A051953, A002496, A039770.
Sequence in context: A062318 A112346 A034445 * A054755 A093331 A162216
Adjacent sequences: A054751 A054752 A054753 * A054755 A054756 A054757
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KEYWORD
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nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Apr 25 2000
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STATUS
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approved
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