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 A241197 Numerator of new minima of phi(p-1)/(p-1), where phi is Euler's totient function and p = prime(n). 3
 1, 1, 1, 4, 8, 16, 288, 256, 192, 768, 384, 3456, 3072, 6912, 6144, 55296, 1658880, 221184, 110592, 3317760, 442368, 13271040 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The values of p are in A241196. The denominator is in A241198. LINKS Table of n, a(n) for n=1..22. EXAMPLE In decimal, the minima are about 1, 0.5, 0.333333, 0.266667, 0.228571, 0.207792, 0.196856, 0.195569, 0.191808, 0.185194, 0.183469, 0.181713, 0.180525, 0.173812, 0.172676, 0.171024, 0.165507, 0.165127, 0.163588. MATHEMATICA tMin = {{2, 1}}; Do[p = Prime[n]; tn = EulerPhi[p - 1]/(p - 1); If[tn < tMin[[-1, -1]], AppendTo[tMin, {p, tn}]], {n, 10^7}]; Numerator[Transpose[tMin][[2]]] CROSSREFS Cf. A008330 (phi(prime(n)-1)), A073918, A241194, A241195. Sequence in context: A242966 A337235 A038110 * A130436 A260306 A031462 Adjacent sequences: A241194 A241195 A241196 * A241198 A241199 A241200 KEYWORD nonn,frac,more AUTHOR T. D. Noe, Apr 17 2014 EXTENSIONS a(20)-a(22) from Giovanni Resta, Apr 14 2016 STATUS approved

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Last modified September 9 11:20 EDT 2024. Contains 375764 sequences. (Running on oeis4.)