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 A075522 Number of steps to reach the first nonprime (=A075523(n)) starting with the n-th prime p and iterating the map k -> 4*k+(p mod 4), or -1 if no integer is ever reached. 2
 1, 1, 1, 3, 3, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 3, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 4, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 3, 1, 1, 1, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS a(A075521(n)) > 1; a(n) = a(A075520(n))+1 for n with A075520(n) prime. LINKS EXAMPLE A000040(4)=7 and (7 mod 4) = 3: 7 -> 4*7+3=31 -> 4*31+3=127 -> 4*127+3=511 = A075523(4), therefore a(4)=3. CROSSREFS Cf. A075520, A075519. Sequence in context: A060574 A283987 A286443 * A186144 A090544 A283755 Adjacent sequences:  A075519 A075520 A075521 * A075523 A075524 A075525 KEYWORD nonn AUTHOR Reinhard Zumkeller, Sep 19 2002 STATUS approved

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Last modified May 31 07:22 EDT 2020. Contains 334747 sequences. (Running on oeis4.)