A068195 Numbers of the form n(n+1)/2 whose only representation as a sum of 2 or more consecutive positive integers is 1+2+...+n.

1, 3, 6, 10, 28, 136, 496, 8128, 32896, 33550336, 2147516416, 8589869056, 137438691328, 2305843008139952128, 2658455991569831744654692615953842176

Offset: 1

Author

Jon Perry, Feb 19 2002

Keywords

• nonn

Comments

Consists of 1, even perfect numbers and numbers of the form n(n+1)/2 where n+1 is a Fermat prime. (See A068194 for proof.)

Links

• Jon Perry, Erdos-Moser

Crossrefs

Cf. A000396, A000668, A019434, A068194.

Record values in A082184.

Extensions

Edited by Dean Hickerson, Feb 22 2002