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 A112815 #15 Jan 31 2021 02:38:16 %S A112815 44,45,46,47,48,301,302,303,304,305,306,307,308,309,310,311,312,313, %T A112815 314,315,316,317,318,319,320,321,322,323,324,325,326,327,328,329,330, %U A112815 331,332,333,334,335,2209,2210,2211,2212,2213,2214,2215,2216,2217,2218,2219 %N A112815 Numbers k such that lcm(1,2,3,...,k)/7 equals the denominator of the k-th harmonic number H(k). %C A112815 When 7 occurs in A110566. %H A112815 Amiram Eldar, <a href="/A112815/b112815.txt">Table of n, a(n) for n = 1..10000</a> %t A112815 f[n_] := LCM @@ Range[n]/Denominator[ HarmonicNumber[n]]; Select[ Range[2219], f[ # ] == 7 &] %o A112815 (PARI) isok(n) = lcm(vector(n, i, i)) == 7*denominator(sum(i=1, n, 1/i)); \\ _Michel Marcus_, Mar 07 2018 %Y A112815 Cf. A002805, A003418, A110566. %Y A112815 Cf. A098464, A112813, A112814, A112816, A112817, A112818, A112819, A112820, A112821, A112822. %K A112815 nonn %O A112815 1,1 %A A112815 _Robert G. Wilson v_, Sep 17 2005