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A348120 Starts of runs of 3 consecutive numbers whose powerful part is larger than their powerfree part (A328014). 2
48, 350, 9800, 11374, 31211, 32798, 48373, 59534, 63000, 103246, 118579, 373827, 488187, 625974, 629693, 830464, 1193983, 1294298, 2989439, 3815174, 4231248, 5132699, 5331248, 6674166, 7616950, 7970157, 8388223, 8670375, 9235520, 9516680, 9841094, 11121382, 12708359 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
There are no runs of 4 consecutive numbers below 10^10.
It is conjectured that there are no runs of 3 consecutive numbers that are powerful (A001694), but if they do exist, their starts are contained in this sequence.
LINKS
EXAMPLE
48 is a term since 48, 49 and 50 are all in A328014.
MATHEMATICA
f[p_, e_] := If[e==1, p, 1]; s[n_] := Times @@ (f @@@ FactorInteger[n]); q[n_] := s[n]^2 < n; v = q /@ Range[3]; seq = {}; Do[v = Append[Drop[v, 1], q[k]]; If[And @@ v, AppendTo[seq, k - 2]], {k, 4, 10^6}]; seq
CROSSREFS
Subsequence of A328014 and A348119.
Cf. A001694.
Sequence in context: A211766 A187164 A110275 * A160335 A019558 A339761
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 01 2021
STATUS
approved

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Last modified April 19 15:34 EDT 2024. Contains 371794 sequences. (Running on oeis4.)