1,2

Sum of the inverses of the tetrahedral numbers (A000292). - Michael B. Porter, Nov 27 2017

Table of n, a(n) for n=1..99.

1.5000000000000000000000000000000000000000000000000000000000...

Cf. A000292 (tetrahedral numbers).

Sums of inverses: A002117 (cubes), A175577 (octahedral numbers), A295421 (dodecahedral numbers), A175578 (icosahedral numbers).

Sequence in context: A336587 A336586 A241471 * A020761 A341881 A281462

Adjacent sequences: A152620 A152621 A152622 * A152624 A152625 A152626

nonn,cons

N. J. A. Sloane, Oct 30 2009

approved