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 A051774 #28 Jun 12 2021 23:19:43 %S A051774 6,12,18,20,24,28,30,36,40,42,45,48,54,56,60,63,66,70,72,78,80,84,88, %T A051774 90,96,99,100,102,104,105,108,110,112,114,117,120,126,130,132,135,138, %U A051774 140,144,150,154,156,160,162,165,168,170,174,175,176,180,182,186 %N A051774 Contracted numbers. %C A051774 n is said to be contracted if and only if n has distinct divisors d_1 < d_2 < ... < d_k such that d_1+d_2+...+d_(k-1) >= d_k. Note that d_k need not be the greatest divisor of n -- see the examples. %H A051774 Alois P. Heinz, <a href="/A051774/b051774.txt">Table of n, a(n) for n = 1..10000</a> %e A051774 6 has divisors 1, 2, 3, 6, and 1+2 >= 3, so 6 is a member. 45 has divisors 1, 3, 5, 9, 15, 45, and 1+3+5+9 = 18 > 15, so 45 is a member. - _N. J. A. Sloane_, Jun 12 2021 %t A051774 cnQ[n_]:=Module[{d=Divisors[n],len},len=Length[d];AnyTrue[Table[Take[ d,k],{k,3,len}],Total[Most[#]]>=Last[#]&]]; Select[Range[200],cnQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 12 2021 *) %Y A051774 Numbers not in A051772. %K A051774 nonn %O A051774 1,1 %A A051774 Alexander Benjamin Schwartz (QBOB(AT)aol.com), Dec 08 1999