OFFSET
1,11
COMMENTS
An IRDCS of length n is a sequence of n integers s(1),...,s(n) with the property that if s(i)=m for some m then the other terms of the sequence with value m are precisely s(i+k*m) for all k such that i+k*m is in [1,n] and further such that any integer appearing in the sequence appears at least twice. For example, the two IRDCS of length n are 6,9,3,4,5,3,6,4,3,5,9 and its reverse.
REFERENCES
Gerry Myerson, Jacky Poon and Jamie Simpson, Incongruent restricted disjoint covering systems, preprint.
CROSSREFS
KEYWORD
nice,nonn
AUTHOR
Jamie Simpson, Jun 25 2007, corrected Sep 11 2007
STATUS
approved