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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.

A371630 Numbers k that set records in A372720.

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%I A371630 #30 Jun 14 2024 11:34:23
%S A371630 1,2,6,12,30,60,120,210,420,840,1260,1680,2520,4620,9240,13860,18480,
%T A371630 27720,32760,55440,65520,102960,110880,120120,180180,240240,360360,
%U A371630 556920,720720,1081080,1441440,1884960,2162160,2827440,2882880,3063060,3603600,4084080,6126120
%N A371630 Numbers k that set records in A372720.
%C A371630 In other words, numbers k that set records for d(k) - f(k), where d = A000005 and f = A008479.
%C A371630 Largest primorial in this sequence is A002110(4) = 210.
%C A371630 The primorials A002110(0..4) are the only squarefree numbers in this sequence.
%C A371630 {a(n)} \ A002110(0..4) is contained in A126706.
%C A371630 Not a subset of A060735; a(13) = 2520 is not in A060735. Though common for small n, the set of a(n) in A060735 is likely finite; the restriction is connected with the finite number of primorials in the sequence.
%C A371630 Not a subset of A025487 or A055932; a(19) = 32760 is the smallest term without a primorial kernel.
%C A371630 The prime shape of a(n) appears to feature exponents m of prime power factors p^m | a(n) that are nonincreasing as pi(p) increases.
%H A371630 Michael S. Branicky, <a href="/A371630/b371630.txt">Table of n, a(n) for n = 1..67</a> (terms 1..56 from Michael De Vlieger)
%H A371630 Michael De Vlieger, <a href="/A371630/a371630.txt">Prime power decomposition of A371630(n)</a>, n = 1..56.
%e A371630 Table of a(n) and A371634(n) = b(n) for n = 1..20. Asterisks in the a(n) column denote squarefree terms while "+" denotes numbers not in A055932 (i.e., in A080259).
%e A371630    n     a(n)  A067255(a(n))            d(n)-f(n) = b(n)
%e A371630   ------------------------------------------------------
%e A371630    1       1*  1                          1 -  1 =   0
%e A371630    2       2*  2                          2 -  1 =   1
%e A371630    3       6*  2 * 3                      4 -  1 =   3
%e A371630    4      12   2^2 * 3                    6 -  2 =   4
%e A371630    5      30*  2 * 3 * 5                  8 -  1 =   7
%e A371630    6      60   2^2 * 3 * 5               12 -  2 =  10
%e A371630    7     120   2^3 * 3 * 5               16 -  4 =  12
%e A371630    8     210*  2 * 3 * 5 * 7             16 -  1 =  15
%e A371630    9     420   2^2 * 3 * 5 * 7           24 -  2 =  22
%e A371630   10     840   2^3 * 3 * 5 * 7           32 -  4 =  28
%e A371630   11    1260   2^2 * 3^2 * 5 * 7         36 -  6 =  30
%e A371630   12    1680   2^4 * 3 * 5 * 7           40 -  8 =  32
%e A371630   13    2520   2^3 * 3^2 * 5 * 7         48 - 11 =  37
%e A371630   14    4620   2^2 * 3 * 5 * 7 * 11      48 -  2 =  46
%e A371630   15    9240   2^3 * 3 * 5 * 7 * 11      64 -  4 =  60
%e A371630   16   13860   2^2 * 3^2 * 5 * 7 * 11    72 -  6 =  66
%e A371630   17   18480   2^4 * 3 * 5 * 7 * 11      80 -  8 =  72
%e A371630   18   27720   2^3 * 3^2 * 5 * 7 * 11    96 - 12 =  84
%e A371630   19   32760+  2^3 * 3^2 * 5 * 7 * 13    96 - 11 =  85
%e A371630   20   55440   2^4 * 3^2 * 5 * 7 * 11   120 - 20 = 100
%Y A371630 Cf. A000005, A002110, A008479, A055932, A060735, A080259, A126706, A371634, A372720.
%K A371630 nonn,hard
%O A371630 1,2
%A A371630 _Michael De Vlieger_, Jun 04 2024