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 A108319 #14 Nov 20 2024 15:36:02 %S A108319 1,2,3,4,6,7,8,9,12,14,16,18,21,24,27,28,32,36,42,48,49,54,56,63,64, %T A108319 72,81,84,96,98,108,112,126,128,144,147,162,168,189,192,196,216,224, %U A108319 243,252,256,288,294,324,336,343,378,384,392,432,441,448,486,504,512,567 %N A108319 Numbers of the form (2^i)*(3^j)*(7^k), with i, j, k >= 0. %C A108319 Numbers m | 42^e with integer e >= 0. - _Michael De Vlieger_, Aug 22 2019 %C A108319 Sum_{n>=1} 1/a(n) = (2*3*7)/((2-1)*(3-1)*(7-1)) = 7/2. - _Amiram Eldar_, Sep 24 2020 %H A108319 Michael De Vlieger, <a href="/A108319/b108319.txt">Table of n, a(n) for n = 1..10000</a> %F A108319 a(n) ~ exp((6*log(2)*log(3)*log(7)*n)^(1/3)) / sqrt(42). - _Vaclav Kotesovec_, Sep 23 2020 %t A108319 With[{n = 567}, Sort@ Flatten@ Table[2^i * 3^j * 7^k, {i, 0, Log2@ n}, {j, 0, Log[3, n/2^i]}, {k, 0, Log[7, n/(2^i*3^j)]}]] (* _Michael De Vlieger_, Aug 22 2019 *) %o A108319 (PARI) list(lim)=my(v=List(), s, t); for(i=0, logint(lim\=1, 7), t=7^i; for(j=0, logint(lim\t, 3), s=t*3^j; while(s<=lim, listput(v, s); s<<=1))); Set(v) \\ _Charles R Greathouse IV_, Nov 20 2024 %Y A108319 Cf. A051037, A003586, A003591, A003594. %K A108319 nonn,easy %O A108319 1,2 %A A108319 Douglas Winston (douglas.winston(AT)srupc.com), Jun 30 2005