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A375975
Products m of k = 4 consecutive primes p_1..p_k, where only p_1 < m^(1/k).
2
257557397, 490995677, 1314423991, 2445956099, 8756100193, 14406533983, 34491476237, 168268429891, 453178561051, 526847565721, 588771800473, 673542175381, 874245022517, 1129796633837, 1267153039517, 1385645583389, 1742522070781, 2638237130051, 3021997659211, 3389753359877
OFFSET
1,1
COMMENTS
In other words, products m of k = 4 consecutive primes p_1..p_k, where floor(log_p_1 m) >= k but floor(log_p_j m) = k-1, j > 1.
a(n) = m is such that floor(log_p_1 m) = k but floor(log_p_j m) = k-1 for j > 1.
Does not intersect A138637, since for m in A138637, both p_1 and p_2 are smaller than m^(1/k).
LINKS
MATHEMATICA
k = 4; s = {1}~Join~Prime[Range[k - 1]]; Reap[Do[s = Append[Rest[s], Prime[i + k - 1]]; r = Surd[Times @@ s, k]; If[Count[s, _?(# < r &)] == 1, Sow[Times @@ s] ], {i, 120}] ][[-1, 1]]
CROSSREFS
Sequence in context: A204415 A246224 A205934 * A231202 A226448 A250433
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Sep 12 2024
STATUS
approved