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 A340075 The odd part of A340072(n). 10
 1, 1, 1, 3, 1, 1, 1, 9, 5, 3, 1, 3, 1, 5, 3, 27, 1, 5, 1, 9, 5, 3, 1, 9, 7, 1, 25, 15, 1, 3, 1, 81, 3, 9, 15, 15, 1, 11, 1, 27, 1, 5, 1, 9, 5, 7, 1, 27, 11, 21, 9, 3, 1, 25, 1, 45, 11, 15, 1, 9, 1, 9, 25, 243, 3, 3, 1, 27, 7, 3, 1, 45, 1, 5, 21, 33, 15, 1, 1, 81, 125, 21, 1, 15, 9, 23, 15, 27, 1, 15, 5, 21, 9, 13, 33, 81 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Each term a(n) is a multiple of A340149(n), therefore, as both sequences have only positive terms, it follows that if a(n) = 1 then A340149(n) = 1 also, but not necessarily vice versa. LINKS Antti Karttunen, Table of n, a(n) for n = 1..8191 Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537 Index entries for sequences computed from indices in prime factorization FORMULA a(n) = A000265(A340072(n)). a(n) = A339904(n) / A340074(n) = A339904(n) / gcd(A003961(n)-1, A339904(n)). For all n >= 0, a(A019565(n)) = A339901(n). PROG (PARI) A000265(n) = (n>>valuation(n, 2)); A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); }; A340072(n) = { my(x=A003961(n), u=eulerphi(x)); u/gcd(x-1, u); }; A340075(n) = A000265(A340072(n)); CROSSREFS Cf. A000265, A003961, A019565, A339901, A339904, A340072, A340074, A340076 (positions of ones), A340149 (differs from the first time at n=85). Sequence in context: A327564 A243748 A340149 * A307847 A080214 A263383 Adjacent sequences: A340072 A340073 A340074 * A340076 A340077 A340078 KEYWORD nonn AUTHOR Antti Karttunen, Dec 28 2020 STATUS approved

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Last modified November 29 03:03 EST 2023. Contains 367422 sequences. (Running on oeis4.)