A091817 (2*numerator(H(p-3)) -3*denominator(H(p-3)))/p with H(m) = 1 + 1/2 + 1/3 + ...+ 1/m.

-1, 0, 2, 62, 554, 74258, 142682, 2830946, 1448977246, 12576415426, 1857881203154, 64634117421826, 62771945063582, 164497840779865642, 350742295126606034006, 5774653629556529218142, 5647762835059481932498, 12720214895833193424471634

Offset

1,3

Comments

Proposed by Leroy Quet.

Leroy Quet conjectures that the terms are always integral. This is true for p < 3*10^4.

Links

Table of n, a(n) for n=1..18.

Formula

a(n) = (2*A001008(p-3) - 3*A002805(p-3))/p, p prime >= 5.

Prog

(PARI) H(n)=sum(i=1, n, 1/i); forprime(p=3, 100, print1((2*numerator(H(p-3))-3*denominator(H(p-3)))/p, ", "))

Crossrefs

Sequence in context: A296361 A224844 A226421 * A239786 A209183 A200802

Adjacent sequences: A091814 A091815 A091816 * A091818 A091819 A091820

Keyword

sign

Author

Mohammed Bouayoun (bouyao(AT)wanadoo.fr) and Ralf Stephan, Mar 07 2004

Status

approved