Least prime p such that H(n) == 0 (mod p) but H(k) == 0 (mod p) for no 0 < k < n, or 1 if such a prime p does not exist, where H(n) denotes the n-th harmonic number sum_{k=1..n}1/k.

A242223

Least prime p such that H(n) == 0 (mod p) but H(k) == 0 (mod p) for no 0 < k < n, or 1 if such a prime p does not exist, where H(n) denotes the n-th harmonic number sum_{k=1..n}1/k.

Terms

    a(0) =1a(1) =3a(2) =11a(3) =5a(4) =137a(5) =7a(6) =1a(7) =761a(8) =7129a(9) =61a(10) =97a(11) =13a(12) =29a(13) =1049a(14) =41233a(15) =17a(16) =37a(17) =19a(18) =7440427a(19) =11167027a(20) =18858053a(21) =23a(22) =583859a(23) =577a(24) =109a(25) =34395742267a(26) =521a(27) =375035183a(28) =4990290163a(29) =31

External references