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 A070844 a(n) = smallest n-digit number with exactly n divisors, or 0 if no such number exists. 6
 1, 11, 121, 1003, 14641, 100017, 1771561, 10000005, 100020001, 1000000016, 25937424601, 100000000004, 3138428376721, 10000000001344, 100000720001296, 1000000000000006, 45949729863572161, 100000000000000404 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Ray Chandler, Table of n, a(n) for n=1..41 FORMULA If n is a prime < 29 then a(n) = 11^(n-1). - Chandler If n is a prime >= 29 then a(n) = 0. - Vladeta Jovovic, Aug 20 2002 MATHEMATICA For[n=1, n<10, n++, k := 10^(n-1); While[Not[Length[Divisors[k]] == n], k++ ]; Print[k]] (Steinerberger) CROSSREFS Cf. A070845. Sequence in context: A293891 A218262 A006940 * A164327 A080445 A033867 Adjacent sequences:  A070841 A070842 A070843 * A070845 A070846 A070847 KEYWORD base,nonn AUTHOR Amarnath Murthy, May 12 2002 EXTENSIONS a(6)-a(18) from Vladeta Jovovic, Aug 20 2002 a(6) confirmed by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 08 2003 a(7)-a(10) confirmed by Stefan Steinerberger, Feb 06 2006 a(15) corrected, and a(11)-a(14), a(16)-a(18) confirmed by Ray Chandler, Feb 10 2009 Edited by N. J. A. Sloane, Feb 14 2009 at the suggestion of Ray Chandler. STATUS approved

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Last modified April 15 06:12 EDT 2021. Contains 342975 sequences. (Running on oeis4.)