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 A360905 Starts of run of 3 consecutive integers that are all terms of A360902. 3
 7939375, 12799375, 20410623, 30466287, 56661199, 83365119, 105146991, 197479375, 235838223, 259360623, 293380623, 555499375, 657880623, 691579375, 871374591, 871720623, 953280495, 975079375, 996393391, 1032100623, 1047979375, 1096579375, 1348000623, 1355419375 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Amiram Eldar, Table of n, a(n) for n = 1..300 EXAMPLE 7939375 is a term since A034444(7939375) = A005361(7939375) = 4, A034444(7939376) = A005361(7939376) = 4, and A034444(7939377) = A005361(7939377) = 4. MATHEMATICA q[n_] := Module[{e = FactorInteger[n][[;; , 2]]}, Times @@ e == 2^Length[e]]; q[1] = True; seq[kmax_] := Module[{tri = q /@ Range[3], s = {}, k = 4}, While[k < kmax, If[And @@ tri, AppendTo[s, k - 3]]; tri = Join[Rest[tri], {q[k]}]; k++]; s]; seq[10^7] PROG (PARI) is(k) = {my(e = factor(k)[, 2]); prod(i = 1, #e, e[i]) == 2^#e; } lista(kmax) = {my(tri = vector(3, i, is(i)), k = 4); while(k < kmax, if(vecsum(tri) == 3, print1(k-3, ", ")); tri = concat(vecextract(tri, "^1"), is(k)); k++); } CROSSREFS Subsequence of A360902 and A360903. Cf. A005361, A034444. Sequence in context: A210275 A346029 A237338 * A233797 A203504 A233803 Adjacent sequences: A360902 A360903 A360904 * A360906 A360907 A360908 KEYWORD nonn AUTHOR Amiram Eldar, Feb 25 2023 STATUS approved

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Last modified December 3 05:03 EST 2023. Contains 367531 sequences. (Running on oeis4.)