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A237607
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Numbers divisible by a square and which have the same property if any number of rightmost digits is deleted.
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2
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4, 8, 9, 40, 44, 45, 48, 49, 80, 81, 84, 88, 90, 92, 96, 98, 99, 400, 404, 405, 408, 440, 441, 444, 448, 450, 452, 456, 459, 480, 484, 486, 488, 490, 492, 495, 496, 800, 801, 804, 808, 810, 812, 816, 819, 840, 841, 844, 845, 846, 847, 848, 880, 882, 884, 888
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OFFSET
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1,1
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COMMENTS
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This regards the interplay between an endomorphism E on the set N and a number property P. In this case, E(n)=floor(n/10) for n >=10 and E(n)=n otherwise, and the property P is "moebius(n)=0". The goal is to find the numbers whose consecutive images under E all have the property P.
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LINKS
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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,base
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AUTHOR
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STATUS
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approved
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