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 A226899 Numbers n for which Delta(m) < Delta(n) for all m < n, where Delta is Hooley's Delta function A226898. 4

%I

%S 1,2,12,24,120,180,360,720,1260,2520,5040,10080,15120,27720,30240,

%T 50400,55440,65520,83160,110880,166320,221760,277200,332640,360360,

%U 554400,665280,720720,1441440,2162160,3603600,4324320,7207200,8648640,10810800,14414400,21621600

%N Numbers n for which Delta(m) < Delta(n) for all m < n, where Delta is Hooley's Delta function A226898.

%C Not a subsequence of A025487: a(18) = 65520 = 2^4 * 3^2 * 5 * 7 * 13, a(46) = 136936800 = 2^5 * 3^2 * 5^2 * 7 * 11 * 13 * 19, and a(50) = 273873600 = 2^6 * 3^2 * 5^2 * 7 * 11 * 13 * 19. - _Charles R Greathouse IV_, Mar 12 2018

%H Charles R Greathouse IV, <a href="/A226899/b226899.txt">Table of n, a(n) for n = 1..64</a>

%H C. Hooley, <a href="https://doi.org/10.1112/plms/s3-38.1.115">On a new technique and its applications to the theory of numbers</a>, Proc. London Math. Soc. 3 38:1 (1979), pp. 115-151.

%o (PARI) Delta(n)=my(d=divisors(n),r,t); for(i=1,#d\2, t=setsearch(d,d[i]*exp(1)\1, 1); t=if(t, t-i, setsearch(d, d[i]*exp(1)\1)+1-i); if(t>r,r=t)); r

%o r=0; for(n=1,1e9, t=Delta(n); if(t>r, r=t; print1(n", ")))

%Y Cf. A226898, A226900, A002182.

%K nonn

%O 1,2

%A _Charles R Greathouse IV_, Jun 21 2013

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Last modified June 24 16:48 EDT 2019. Contains 324325 sequences. (Running on oeis4.)