login
A115648
Square numbers which are the sum of distinct double factorials (A006882).
2
1, 4, 9, 16, 25, 49, 64, 121, 169, 400, 441, 961, 1444, 3844, 3969, 4225, 4356, 4900, 5184, 10404, 11449, 11881, 14400, 15625, 47089, 47524, 56644, 57600, 139129, 145924, 149769, 182329, 192721, 695556, 705600, 792100, 837225, 2073600
OFFSET
1,2
COMMENTS
Double factorials 0!! and 1!! are not considered distinct. Note that double factorial (n!!) is different from (n!)!.
EXAMPLE
10404 = 102^2 = 1!! + 4!! + 11!!.
CROSSREFS
KEYWORD
nonn
AUTHOR
Giovanni Resta, Jan 28 2006
STATUS
approved