+77 Let A={2,6,10,14,...} be the set of integers that are twice an odd number.
Prove that, for every positive integer n, the number of partitions of n in which no odd number appears more than once is equal to the number of partitions of n containing no element of A.
For example, for n=6, the partitions of the first type are
6,5+1,4+2,3+2+1,2+2+2 and the partitions of the second type are
5+1,4+1+1,3+3,3+1+1+1,1+1+1+1+1+1,and there are 5 of each type.
