This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A379447 #6 Dec 26 2024 12:34:56 %S A379447 1,1,8,1,19,27,68,1,128,105,209,120,320,266,442,1,584,524,774,476, %T A379447 1006,833,1188,477,1486,1248,1746,1066,2068,1733,2365,1,2735,2328, %U A379447 3134,1982,3598,3085,4062,1823,4415,3937,5038,3309,5571,4808,6137,1790,6794,5768,7381 %N A379447 a(n) is the number of ones in the binary expansion of (n^n)^n. %F A379447 a(2^k) = 1. %e A379447 a(3) = 8: (3^3)^3 = 27^3 = 19683 = 100110011100011_2 which has 8 ones. %t A379447 Array[DigitCount[#^(#^2), 2, 1] &, 50] (* _Michael De Vlieger_, Dec 26 2024 *) %o A379447 (PARI) a379447(n) = hammingweight((n^n)^n) %Y A379447 Cf. A000120, A002489, A379448. %K A379447 nonn,base %O A379447 1,3 %A A379447 _Hugo Pfoertner_, Dec 26 2024