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 A245087 Largest number such that 2^a(n) is a divisor of (n!)!. 2
 0, 0, 1, 4, 22, 116, 716, 5034, 40314, 362874, 3628789, 39916793, 479001588, 6227020788, 87178291188, 1307674367982, 20922789887982, 355687428095978, 6402373705727977, 121645100408831983, 2432902008176639978, 51090942171709439975, 1124000727777607679972 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Also the number of trailing zeros in the binary expansion of (n!)!. LINKS Stanislav Sykora, Table of n, a(n) for n = 0..399 FORMULA a(n) = n! - Hw(n!), Hw being the Hamming weight function. a(n) = A011371(A000142(n)). EXAMPLE a(4)=22 because (4!)!=620448401733239439360000 is divisible by 2^22 but not by 2^23. PROG (PARI) a(n) = n!-hammingweight(n!) CROSSREFS Cf. A000120 (Hamming weights), A000142, A000197, A011371. Sequence in context: A293966 A305554 A291183 * A155596 A244900 A261193 Adjacent sequences:  A245084 A245085 A245086 * A245088 A245089 A245090 KEYWORD nonn AUTHOR Stanislav Sykora, Jul 15 2014 STATUS approved

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Last modified September 23 00:32 EDT 2021. Contains 347609 sequences. (Running on oeis4.)