A330742 -id:A330742 - cp's OEIS frontend

A330691 a(n) = gcd(n, A309639(n)), where A309639(n) is the index of the least harmonic number H_i whose denominator (A002805) is divisible by n.

1, 2, 3, 4, 5, 3, 7, 8, 9, 5, 11, 4, 13, 7, 5, 16, 17, 9, 19, 5, 3, 11, 23, 3, 25, 13, 27, 7, 29, 5, 31, 32, 11, 17, 7, 9, 37, 19, 13, 8, 41, 3, 43, 11, 9, 23, 47, 16, 49, 25, 17, 13, 53, 27, 11, 8, 19, 29, 59, 5, 61, 31, 9, 64, 13, 11, 67, 17, 3, 7, 71, 9, 73, 37, 25, 19, 11, 13, 79, 16, 81, 41, 83, 3, 17, 43, 29, 11, 89, 9

Offset: 1

Antti Karttunen, Dec 29 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..65537

Cf. A000961 (fixed points).

Cf. A002805, A309639, A330692, A330742.

A309639[n_] := For[k = 1, True, k++, If[Divisible[Denominator[ HarmonicNumber[k]], n], Return[k]]];
a[n_] := GCD[n, A309639[n]];
Array[a, 105]

PARI
```
A330691(n) = gcd(n, A309639(n));
```

a(n) = gcd(n, A309639(n)).

a(n) = n/A330692(n).

A330692 a(n) = n / gcd(n, A309639(n)), where A309639(n) is the index of the least harmonic number H_i whose denominator (A002805) is divisible by n.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 1, 2, 3, 1, 1, 2, 1, 4, 7, 2, 1, 8, 1, 2, 1, 4, 1, 6, 1, 1, 3, 2, 5, 4, 1, 2, 3, 5, 1, 14, 1, 4, 5, 2, 1, 3, 1, 2, 3, 4, 1, 2, 5, 7, 3, 2, 1, 12, 1, 2, 7, 1, 5, 6, 1, 4, 23, 10, 1, 8, 1, 2, 3, 4, 7, 6, 1, 5, 1, 2, 1, 28, 5, 2, 3, 8, 1, 10, 7, 4, 3, 2, 5, 3, 1, 2, 9, 4, 1, 6, 1, 8, 35

Offset: 1

Antti Karttunen, Dec 29 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..65537

Cf. A000961 (indices of 1's).

Cf. A002805, A309639, A330691, A330742.

PARI
```
A330692(n) = (n/gcd(n, A309639(n)));
```

a(n) = n/A330691(n) = n / gcd(n, A309639(n)).

A330741 a(n) = gcd(A309639(n), A319626(n)).

Original entry on oeis.org

1, 2, 3, 4, 5, 3, 7, 8, 9, 5, 11, 2, 13, 7, 5, 16, 17, 9, 19, 5, 3, 11, 23, 3, 25, 13, 27, 7, 29, 5, 31, 32, 11, 17, 7, 9, 37, 19, 13, 8, 41, 3, 43, 11, 3, 23, 47, 8, 49, 25, 17, 13, 53, 27, 11, 8, 19, 29, 59, 5, 61, 31, 9, 64, 13, 11, 67, 17, 3, 7, 71, 9, 73, 37, 25, 19, 11, 13, 79, 16, 81, 41, 83, 3, 17, 43, 29, 11, 89, 3

Offset: 1

Antti Karttunen, Dec 29 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..65537

Cf. A309639, A319626, A330742, A330749.

A330741(n) = gcd(A309639(n), A319626(n));

a(n) = gcd(A309639(n), A319626(n)).

a(n) = n / A330742(n).

cp's OEIS Frontend

A330691 a(n) = gcd(n, A309639(n)), where A309639(n) is the index of the least harmonic number H_i whose denominator (A002805) is divisible by n.

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PARI

Formula

A330692 a(n) = n / gcd(n, A309639(n)), where A309639(n) is the index of the least harmonic number H_i whose denominator (A002805) is divisible by n.

Views

Author

Keywords

Links

Crossrefs

Programs

PARI

Formula

A330741 a(n) = gcd(A309639(n), A319626(n)).

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Author

Keywords

Links

Crossrefs

Programs

PARI

Formula