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 A241490 Least zeroless number k such that k^3 contains n zeros. 0
 16, 52, 126, 252, 3138, 5852, 58752, 71138, 493352, 1916568, 11696559, 58633193, 191293929, 464296543, 386826983, 5886958939, 46493141317, 115356679131, 79633784516, 2154578383152, 6694429222569 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..21. EXAMPLE 16 does not have a 0 but 16^3 = 4096 has 1 zero. So, a(1) = 16. 52 does not have a 0 but 52^3 = 140608 has 2 zeros. So, a(2) = 52. PROG (Python) def Cu(n): ..k = 0 ..while k < 10**50: ....if str(k).count("0") > 0: ......c = [] ......d = '' ......for i in list(str(k).partition("0")): ........if int(i) == 0: ..........c.append('1'*len(i)) ........else: ..........c.append(i) ......for j in c: ........d += j ......k = int(d) ....if str(k**3).count("0") == n: ......return k ....else: ......k += 1 n = 1 while n < 50: ..print(Cu(n)) ..n += 1 CROSSREFS Cf. A052382. Sequence in context: A009953 A009939 A009935 * A009931 A009936 A217736 Adjacent sequences: A241487 A241488 A241489 * A241491 A241492 A241493 KEYWORD nonn,more,base,hard AUTHOR Derek Orr, Apr 23 2014 EXTENSIONS a(17)-a(21) from Giovanni Resta, Apr 27 2014 STATUS approved

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Last modified July 21 15:18 EDT 2024. Contains 374474 sequences. (Running on oeis4.)