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 A180277 a(n) = A002952(n) + A002953(n). 1
 240, 2400, 40320, 72576, 94080, 120960, 141120, 311040, 403200, 483840, 483840, 725760, 673920, 1010880, 1209600, 1497600, 1411200, 1612800, 1747200, 2246400, 2177280, 2371200, 2449440, 2419200, 2620800, 2903040, 3144960, 3110400 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..7896 FORMULA a(n) = A002952(n) + A002953(n). {(j+k) such that sigma*(j) = sigma*(k) = j+k, where sigma*(n) is the unitary divisor function A034448}. EXAMPLE a(1) = 114 + 126 = 240 = 2^4 * 3 * 5. a(2) = 1140 + 1260 = 2400 = 2^5 * 3 * 5^2. a(10) = a(11) - why? CROSSREFS Cf. A002952, A002953, A161005, A180163. Sequence in context: A049335 A004009 A269033 * A357257 A005950 A279746 Adjacent sequences: A180274 A180275 A180276 * A180278 A180279 A180280 KEYWORD nonn,less,changed AUTHOR Jonathan Vos Post, Aug 23 2010 EXTENSIONS Extended by R. J. Mathar, Aug 26 2010 Shorter name using given formula from Joerg Arndt, Jul 29 2024 STATUS approved

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Last modified August 10 09:30 EDT 2024. Contains 375044 sequences. (Running on oeis4.)