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

1, 2, 12, 24, 120, 180, 360, 720, 1260, 2520, 5040, 10080, 15120, 27720, 30240, 50400, 55440, 65520, 83160, 110880, 166320, 221760, 277200, 332640, 360360, 554400, 665280, 720720, 1441440, 2162160, 3603600, 4324320, 7207200, 8648640, 10810800, 14414400, 21621600

Offset

1,2

Comments

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

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..64

C. Hooley, On a new technique and its applications to the theory of numbers, Proc. London Math. Soc. 3 38:1 (1979), pp. 115-151.

Prog

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

Crossrefs

Cf. A226898, A226900, A002182.

Sequence in context: A247086 A337077 A121119 * A309278 A052565 A176710

Adjacent sequences: A226896 A226897 A226898 * A226900 A226901 A226902

Keyword

nonn

Author

Charles R Greathouse IV, Jun 21 2013

Status

approved