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A074493 Numbers n such that all the divisors of n appear as substrings in n^3. 0
1, 5, 25, 49, 125, 251, 499, 751, 1249, 4999, 18229, 31249, 49999, 281249, 4218751, 4999999, 9590417, 31622777, 68171507, 74218751, 574218751, 5740883989, 8829261293 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..23.

EXAMPLE

The divisors of 125 are 1, 5, 25, 125, which appear as substrings in 1953125, so 125 is a term of the sequence.

MATHEMATICA

a = {}; Do[d = Divisors[i]; l = Length[d]; r = True; s = ToString[i^3]; For[j = 1, j <= l, j++, If[StringPosition[s, ToString[d[[j]]]] == {}, r = False; Break] ]; If[r == True, a = Append[a, i]], {i, 1, 10^5}]; a

CROSSREFS

Sequence in context: A273789 A147176 A298041 * A262760 A290700 A136914

Adjacent sequences:  A074490 A074491 A074492 * A074494 A074495 A074496

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe, Sep 25 2002

EXTENSIONS

a(15)-a(23) from Donovan Johnson, Dec 13 2010

STATUS

approved

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Last modified July 5 17:29 EDT 2020. Contains 335473 sequences. (Running on oeis4.)