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 A351084 a(n) = gcd(n, A328572(n)), where A328572 converts the primorial base expansion of n into its prime product form, but with 1 subtracted from all nonzero digits. 6
 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 5, 1, 1, 1, 1, 25, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 25, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 5, 1, 7, 1, 1, 5, 1, 1, 1, 7, 5, 1, 1, 1, 1, 1, 7, 1, 1, 1, 1, 1, 1, 49, 1, 1, 1, 1, 1, 1, 35 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,16 LINKS Antti Karttunen, Table of n, a(n) for n = 0..65537 Index entries for sequences related to primorial base FORMULA a(n) = gcd(n, A328572(n)) = gcd(A324198(n), A351083(n)). a(n) = gcd(n, A085731(A276086(n))) = gcd(n, A276086(n), A327860(n)). PROG (PARI) A328572(n) = { my(m=1, p=2); while(n, if(n%p, m *= p^((n%p)-1)); n = n\p; p = nextprime(1+p)); (m); }; A351084(n) = gcd(n, A328572(n)); (PARI) A351084(n) = { my(m=1, p=2, orgn=n); while(n, if(n%p, m *= (p^min((n%p)-1, valuation(orgn, p)))); n = n\p; p = nextprime(1+p)); (m); }; CROSSREFS Cf. A003415, A276086, A324198, A327860, A328572, A351080, A351083. Sequence in context: A129398 A109009 A060904 * A135469 A348735 A170817 Adjacent sequences: A351081 A351082 A351083 * A351085 A351086 A351087 KEYWORD nonn,easy AUTHOR Antti Karttunen, Feb 03 2022 STATUS approved

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Last modified September 18 03:51 EDT 2024. Contains 375995 sequences. (Running on oeis4.)