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 A181062 Prime powers minus 1. 9
 0, 1, 2, 3, 4, 6, 7, 8, 10, 12, 15, 16, 18, 22, 24, 26, 28, 30, 31, 36, 40, 42, 46, 48, 52, 58, 60, 63, 66, 70, 72, 78, 80, 82, 88, 96, 100, 102, 106, 108, 112, 120, 124, 126, 127, 130, 136, 138, 148, 150, 156, 162, 166, 168, 172, 178, 180, 190, 192, 196, 198, 210, 222, 226 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS If 0 is excluded, a(n) gives the possible lengths of the longest string of consecutive divisors of a positive integer: range of values of A055874. a(n) = largest number m such that A051451(n) = A003418(m). LINKS Matthew House, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A000961(n)-1. EXAMPLE Any integer that is divisible by 5 consecutive integers will be divisible by at least 6 consecutive integers. Hence 5 is not in the sequence. MATHEMATICA Select[Table[n, {n, 1, 350}], Length[FactorInteger[#]] == 1 &] - 1 (* Vladimir Joseph Stephan Orlovsky, Jun 28 2011 *) Join[{0}, Select[Range@225, PrimePowerQ] - 1] (* Ivan Neretin, Aug 04 2016 *) PROG (PARI) isA181062(n)=ispower(n++, , &n); isprime(n) \\ Charles R Greathouse IV, Jun 29 2011 (PARI) isok(n) = (n==0) || isprimepower(n++); \\ Michel Marcus, Aug 05 2016 CROSSREFS Cf. A000961, A181063, A181064, A181121. Includes A006093 as a subsequence. Cf. A003418, A051451, A055874. Sequence in context: A221178 A080389 A226038 * A091199 A093452 A082103 Adjacent sequences:  A181059 A181060 A181061 * A181063 A181064 A181065 KEYWORD easy,nonn AUTHOR Matthew Vandermast, Oct 07 2010 EXTENSIONS Entry revised by N. J. A. Sloane, Jan 06 2013 STATUS approved

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Last modified October 15 07:56 EDT 2019. Contains 328026 sequences. (Running on oeis4.)