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A072938 Highly composite numbers that are half of the next highly composite number. 12 1, 2, 6, 12, 60, 360, 2520 (list; graph; refs; listen; history; text; internal format) OFFSET 1,2 COMMENTS A002182(k) such that A002182(k+1) = 2*A002182(k). Numbers m such that d(m)>=d(k) for 0<k<2m {d(n) being the number of divisors function: A000005(n)}. - Lekraj Beedassy, Dec 16 2004 W. Brefeld (cf. link) gives a proof that there are no other terms. - Klaus Brockhaus, Mar 05 2006 LINKS Table of n, a(n) for n=1..7. Werner Brefeld, Ramanujan, zusammengesetzte Zahlen und ihre Teilbarkeit. Achim Flammenkamp, Highly Composite Numbers. EXAMPLE 6 = A002182(4) is a term since A002182(5) = 12 = 2*6. CROSSREFS Cf. A002110, A002182, A002201, A003418, A094348, A106037, A165412. Sequence in context: A335831 A189394 A182862 * A160274 A048803 A068625 Adjacent sequences: A072935 A072936 A072937 * A072939 A072940 A072941 KEYWORD nonn,fini,full AUTHOR Anonymous, Aug 12 2002 EXTENSIONS Edited by Klaus Brockhaus, Aug 13 2002 STATUS approved

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Last modified July 18 06:54 EDT 2024. Contains 374377 sequences. (Running on oeis4.)