A336848 a(n) = A003973(n) / A336846(n).

1, 2, 3, 13, 4, 2, 6, 10, 31, 8, 7, 13, 9, 4, 12, 121, 10, 62, 12, 52, 18, 14, 15, 2, 19, 6, 39, 26, 16, 8, 19, 182, 21, 20, 24, 403, 21, 8, 27, 40, 22, 12, 24, 7, 124, 10, 27, 121, 133, 38, 6, 13, 30, 26, 4, 20, 36, 32, 31, 52, 34, 38, 62, 1093, 36, 14, 36, 130, 9, 16, 37, 62, 40, 14, 57, 52, 42, 18, 42, 484, 781

Offset

1,2

Comments

If there are no more 1's in this sequence after the initial one, then there are no odd terms of A001599 (Ore's Harmonic Numbers) larger than one.

Links

Antti Karttunen, Table of n, a(n) for n = 1..16383

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

Formula

a(n) = A003973(n) / A336846(n).

Prog

(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A336848(n) = { my(u=A003961(n), s=sigma(u)); (s/gcd(s, numdiv(n)*u)); };

Crossrefs

Cf. A000005, A000203, A001599, A003961, A003973, A336845, A336846, A336847, A336849.

Sequence in context: A362289 A345040 A196378 * A336838 A051298 A069870

Adjacent sequences: A336845 A336846 A336847 * A336849 A336850 A336851

Keyword

nonn

Author

Antti Karttunen, Aug 06 2020

Status

approved