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 A138572 Numbers k that divide the sum of the digits of k^k in base 2. 0
 1, 6, 122, 2126, 7910, 8254, 16201, 32312, 32426, 32998, 65436, 261649, 261803, 1044017, 1050183 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Conjecture: the sequence is infinite. The quotients are 1, 1, 3, 5, 6, 6, 7, 6, 7, 7, 7, 9, 9, 10, 10. LINKS EXAMPLE 6^6 = 1011011001000000_2; 1+0+1+1+0+1+1+0+0+1+0+0+0+0+0+0 = 6; 6 mod 6 = 0. MATHEMATICA Select[Range[1100000], Divisible[Total[IntegerDigits[#^#, 2]], #]&] (* Harvey P. Dale, Dec 18 2014 *) PROG (PARI) isok(k) = !(hammingweight(k^k) % k); \\ Michel Marcus, Aug 20 2021 CROSSREFS Cf. A108827. Sequence in context: A336808 A296801 A249168 * A078261 A239752 A193223 Adjacent sequences:  A138569 A138570 A138571 * A138573 A138574 A138575 KEYWORD base,hard,more,nonn AUTHOR Robert Gerbicz, May 12 2008 EXTENSIONS a(12)-a(15) from Lars Blomberg, Jul 01 2011 STATUS approved

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Last modified May 18 10:28 EDT 2022. Contains 353807 sequences. (Running on oeis4.)