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A037992
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Smallest number with 2^n divisors.
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15
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1, 2, 6, 24, 120, 840, 7560, 83160, 1081080, 17297280, 294053760, 5587021440, 128501493120, 3212537328000, 93163582512000, 2888071057872000, 106858629141264000, 4381203794791824000, 188391763176048432000
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(n)= A052330(2^n -1). - Tomasz Ordowski (ordot(AT)poczta.onet.pl), Jun 29 2005
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..100
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FORMULA
| a(n)=product of the first n entries of A050376(n). - Lekraj Beedassy (blekraj(AT)yahoo.com), Jun 30 2004
A001221(a(n+1))<=A001221(a(n))+1, see also A074239; A007847(a(n)) are primorials (A002110) in nondecreasing order. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Apr 16 2006
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PROG
| (PARI) {a(n)= local(A, m, c, k, p); if(n<1, n==0, c=0; A=1; m=1; while( c<n, m++; if( isprime(m)| ( (k=ispower(m, (null), &p))&isprime(p)& k ==2^valuation(k, 2) ), A*=m; c++)); A)} /* Michael Somos Apr 15 2005 */
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CROSSREFS
| A000005(a(n))=A000079(n).
Sequence in context: A114790 A079854 A024923 * A114779 A144167 A104983
Adjacent sequences: A037989 A037990 A037991 * A037993 A037994 A037995
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KEYWORD
| nonn,nice
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AUTHOR
| J. Lowell (jhbubby(AT)avana.net)
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EXTENSIONS
| More terms from Don Reble (djr(AT)nk.ca), Aug 20 2002
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