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 A272329 Indices of records in A272328. 0
 1, 3, 16, 15, 35, 39, 45, 91, 111, 117, 135, 364, 287, 296, 292, 273, 369, 385, 429, 482, 465, 866, 819, 861, 915, 964, 1154, 1209, 1281, 1558, 1448, 1395, 1845, 1928, 2432, 2336, 2308, 2306, 2275, 2379, 3472, 3416, 3285, 3344, 2583, 3224, 2715, 2775, 2896, 3003 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..50. MATHEMATICA t = Table[Count[Range@ n, k_ /; EulerPhi@ n == EulerPhi[n + k]], {n, 3600}]; TakeWhile[Flatten[FirstPosition[t, #] & /@ Range@ Max@ t] /. n_ /; MissingQ@ n -> 0, # != 0 &] (* Michael De Vlieger, Apr 25 2016, Version 10.2 *) PROG (Sage) L=[sum([1 for k in [1..n] if euler_phi(n)==euler_phi(n+k)]) for n in [1..4000]] print([L.index(i)+1 for i in [1..50]]) CROSSREFS Cf. A272328, A081375. Sequence in context: A320543 A213847 A195883 * A076623 A068516 A219508 Adjacent sequences: A272326 A272327 A272328 * A272330 A272331 A272332 KEYWORD nonn AUTHOR Tom Edgar, Apr 25 2016 STATUS approved

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Last modified March 2 05:08 EST 2024. Contains 370460 sequences. (Running on oeis4.)