OFFSET
1,5
COMMENTS
Sequence A083956 becomes "unnatural" for n>9. It is easily seen that for n=2k, the sum of permutations A124797(n) is {k:n}0 in base n+1 where {k:n} means n times the digit k; while for n=2k+1 (>1), the sum is k{n:2k}{k+1} (again in base n+1). In particular, this number has n+1 digits (for n>1), such that the digits for A124797(n) start at place n(n+1)/2-1 (for n>1).
EXAMPLE
a(1)=1, the sum of cyclic permutations of 1;
a(2..4)=0,1,1 since 12 + 21 = 110 in base 3;
a(5..8)=2,3,3,1 since 123 + 231 + 312 = 1332 in base 4;
a(9..13)=0,2,2,2,2 since 1234 + 2341 + 3412 + 4123 = 22220 in base 5.
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
M. F. Hasler, Nov 07 2006
STATUS
approved