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Primes p such that there is an integer k satisfying p = floor(k*H(k)) where H(k) denotes the k-th harmonic number (i.e., H(k) = 1 + 1/2 + 1/3 + ... + 1/k).
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%I #8 Jul 29 2017 21:27:55

%S 2,3,5,11,29,37,41,67,71,149,181,191,197,229,241,251,257,307,353,359,

%T 383,389,401,443,449,461,479,521,557,563,569,647,653,661,673,743,769,

%U 787,827,887,1033,1129

%N Primes p such that there is an integer k satisfying p = floor(k*H(k)) where H(k) denotes the k-th harmonic number (i.e., H(k) = 1 + 1/2 + 1/3 + ... + 1/k).

%e 10*Sum_{j=1..10} 1/j = 29.2896825..., hence 29 = floor(10*H(10)) and 29 is in the sequence.

%K nonn

%O 1,1

%A _Benoit Cloitre_, Jan 13 2003