A332561 a(n) = A332560(n)/A332559(n).

20, 20, 10, 105, 1512, 27720, 4620, 660, 144144, 16016, 5445440, 495040, 12697776, 976752, 69768, 823727520, 51482970, 3028410, 168245, 8855, 159845400, 5768642880, 262211040, 11400480, 475020, 543814622208, 20915947008, 774664704, 941432800

Offset: 1

Author

Scott R. Shannon and N. J. A. Sloane, Feb 24 2020

Keywords

• nonn
• look

Links

• Jinyuan Wang, Table of n, a(n) for n = 1..10000
• J. S. Myers, R. Schroeppel, S. R. Shannon, N. J. A. Sloane, and P. Zimmermann, Three Cousins of Recaman's Sequence, arXiv:2004:14000 [math.NT], April 2020.

Crossrefs

Cf. A061836, A332558, A332559, A332560.

Programs

PARI

A332558(n) = {my(r=n*(n+1)); for(k=2, oo, r=r*(n+k); if(r%(n+k+1)==0, return(k))); }
a(n) = {my(s=A332558(n)+n); s!/(n-1)!/(s+1); } \\ Jinyuan Wang, Feb 25 2020