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A237608
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Number of n-digit numbers that are divisible by a square and have the same property if any number of rightmost digits is deleted.
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0
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3, 14, 61, 263, 1128, 4788, 20271, 85885, 364408, 1546394, 6563924, 27863816, 118286561
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listen;
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OFFSET
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1,1
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COMMENTS
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See A237607 for the numbers themselves and for more comments.
The ratio r(n) = a(n+1)/a(n) seems to converge to a constant value of about 4.245...
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LINKS
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EXAMPLE
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One-digit numbers k with moebius(k)=0 are 4, 8 and 9. Hence a(1) = 3.
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PROG
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(PARI) See the link (use GT_DivMod0 with "IsMoebiusZero" for the "property" argument).
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CROSSREFS
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KEYWORD
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nonn,hard,more,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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