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 A237608 Number of n-digit numbers that are divisible by a square and have the same property if any number of rightmost digits is deleted. 0
 3, 14, 61, 263, 1128, 4788, 20271, 85885, 364408, 1546394, 6563924, 27863816, 118286561 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS 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... LINKS Stanislav Sykora, PARI/GP scripts for genetic threads EXAMPLE One-digit numbers k with moebius(k)=0 are 4, 8 and 9. Hence a(1) = 3. PROG (PARI) See the link (use GT_DivMod0 with "IsMoebiusZero" for the "property" argument). CROSSREFS Cf. A237607. Sequence in context: A006502 A024037 A281349 * A100295 A091701 A242637 Adjacent sequences:  A237605 A237606 A237607 * A237609 A237610 A237611 KEYWORD nonn,hard,more,base AUTHOR Stanislav Sykora, Feb 15 2014 EXTENSIONS a(12)-a(13) from Lars Blomberg, Jan 02 2016 STATUS approved

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