A101755 Indices of highly composite triangular numbers.

1, 2, 3, 7, 8, 15, 24, 32, 35, 63, 80, 104, 224, 384, 560, 935, 1224, 1664, 1728, 2015, 2079, 5984, 12375, 14399, 21735, 41040, 78624, 98175, 123200, 126224, 165375, 201824, 313599, 395199, 453375, 1056159, 1154439, 1324224, 1890944, 2203200, 2756159, 6969599

Offset: 1

Author

Ray Chandler, Dec 22 2004

Keywords

• nonn

Links

• Charles R Greathouse IV and Donovan Johnson, Table of n, a(n) for n = 1..70 (first 55 terms from _Charles R Greathouse IV_).

Crossrefs

Cf. A076711, A101756.

Programs

PARI

r=0;for(n=1,1e7,t=if(n%2,numdiv(n)*numdiv((n+1)/2),numdiv(n/2)*numdiv(n+1));if(t>r,r=t;print1(n", "))) \\ Charles R Greathouse IV, Feb 01 2013

Formula

A000217(a(n)) = A076711(n).