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 A076533 Numbers n such that sum of the distinct prime factors of phi(n) = sum of the distinct prime factors of sigma(n). 10
 1, 3, 14, 35, 42, 70, 105, 119, 209, 210, 238, 248, 297, 357, 412, 418, 477, 594, 595, 616, 627, 714, 744, 954, 1045, 1142, 1178, 1190, 1236, 1240, 1254, 1328, 1339, 1463, 1485, 1672, 1674, 1703, 1736, 1785, 1848, 1863, 2079, 2090, 2376, 2385, 2540, 2728 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 EXAMPLE sopf(sigma(14)) = 5; sopf(phi(14))) = 5; hence 14 is a term of the sequence. MATHEMATICA p[n_] := Apply[Plus, Transpose[FactorInteger[n]][[1]]]; Select[Range[3, 10^4], p[DivisorSigma[1, # ]] == p[EulerPhi[ # ]] &] Select[Range[3000], Total[FactorInteger[DivisorSigma[1, #]][[All, 1]]] == Total[ FactorInteger[EulerPhi[#]][[All, 1]]]&] (* Harvey P. Dale, Sep 20 2016 *) PROG (PARI) sopf(n)=my(f=factor(n)[, 1]); sum(i=1, #f, f[i]) is(n)=sopf(sigma(n))==sopf(eulerphi(n)) \\ Charles R Greathouse IV, Mar 09 2014 CROSSREFS Cf. A008472, A075565, A075784, A075846, A076525, A076527, A076531, A076532. Sequence in context: A077288 A094627 A009394 * A081379 A081377 A050934 Adjacent sequences: A076530 A076531 A076532 * A076534 A076535 A076536 KEYWORD nonn AUTHOR Joseph L. Pe, Oct 18 2002 EXTENSIONS Edited by Ray Chandler, Feb 13 2005 a(1) inserted by Charles R Greathouse IV, Mar 09 2014 STATUS approved

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Last modified May 30 13:17 EDT 2023. Contains 363050 sequences. (Running on oeis4.)