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 A100762 Let n = 2^e_2 * 3^e_3 * 5^e_5 * ... be the prime factorization of n and let P(n) = A100549(n); then a(n) = Product_{ q <= P(n) } q^e_q; a(1) = 1 by convention. 8
 1, 2, 1, 4, 1, 2, 1, 8, 9, 2, 1, 12, 1, 2, 1, 16, 1, 18, 1, 4, 1, 2, 1, 24, 1, 2, 27, 4, 1, 2, 1, 32, 1, 2, 1, 36, 1, 2, 1, 8, 1, 2, 1, 4, 9, 2, 1, 48, 1, 2, 1, 4, 1, 54, 1, 8, 1, 2, 1, 12, 1, 2, 9, 64, 1, 2, 1, 4, 1, 2, 1, 72, 1, 2, 3, 4, 1, 2, 1, 80, 81, 2, 1, 12, 1, 2, 1, 8, 1, 18, 1, 4, 1, 2, 1, 96, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Antti Karttunen, Table of n, a(n) for n = 1..16384 Antti Karttunen, Data supplement: n, a(n) computed for n = 1..100000 MAPLE # First load the procedure pp from A100549 # B = prod_{p <= pp(n)} p^e_p B := proc(n) local v, f, pv; global pp; option remember; pv := pp(n); v := 1: for f in op(2..-1, ifactors(n)) while f[1] <= pv do v := v * f[1]^f[2]; end do; return v; end proc; MATHEMATICA {1}~Join~Array[Function[{q, P}, Times @@ Power @@@ Select[q, First@# <= P &]] @@ {#, Prime@ PrimePi[1 + Max@ #[[All, -1]] ]} &@ FactorInteger[#] &, 96, 2] (* Michael De Vlieger, Nov 13 2018 *) PROG (PARI) A100549(n) = if(1==n, 1, prime(primepi(1+vecmax(factor(n)[, 2])))); A100762(n) = if(1==n, 1, my(u = A100549(n), f=factor(n)); prod(i=1, #f~, if(f[i, 1]<=u, f[i, 1]^f[i, 2], 1))); \\ Antti Karttunen, Nov 11 2018 CROSSREFS Cf. A100549, A100417, A141586, A082725. Sequence in context: A108738 A064405 A235872 * A059147 A091891 A258127 Adjacent sequences:  A100759 A100760 A100761 * A100763 A100764 A100765 KEYWORD nonn AUTHOR David Applegate and N. J. A. Sloane, Sep 15 2008 STATUS approved

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Last modified May 9 00:09 EDT 2021. Contains 343685 sequences. (Running on oeis4.)