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 A328839 Smallest prime not dividing n times smallest prime not dividing A276087(n). 2
 4, 15, 4, 21, 4, 25, 4, 21, 4, 33, 4, 15, 4, 33, 4, 21, 4, 25, 4, 39, 4, 39, 4, 15, 4, 39, 4, 51, 4, 21, 4, 21, 4, 15, 4, 25, 4, 33, 4, 39, 4, 15, 4, 39, 4, 39, 4, 25, 4, 51, 4, 51, 4, 15, 4, 51, 4, 33, 4, 21, 4, 33, 4, 21, 4, 25, 4, 39, 4, 39, 4, 15, 4, 51, 4, 51, 4, 25, 4, 51, 4, 57, 4, 15, 4, 39, 4, 57, 4, 21, 4, 39, 4, 51, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Antti Karttunen, Table of n, a(n) for n = 1..32768 Index entries for sequences related to primorial numbers FORMULA a(n) = A053669(n) * A328579(n). PROG (PARI) A053669(n) = forprime(p=2, , if(n%p, return(p))); \\ From A053669 A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); }; A328579(n) = A053669(A276086(A276086(n))); A328839(n) = (A053669(n) * A328579(n)); CROSSREFS Cf. A010709 (odd bisection), A053669, A276086, A276087, A328578, A328579. Cf. A328585 (positions of the prime squares). Sequence in context: A128235 A357116 A024547 * A143899 A154068 A309526 Adjacent sequences: A328836 A328837 A328838 * A328840 A328841 A328842 KEYWORD nonn AUTHOR Antti Karttunen, Oct 29 2019 STATUS approved

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Last modified October 1 12:35 EDT 2023. Contains 365826 sequences. (Running on oeis4.)