OFFSET
2,1
EXAMPLE
2 23 24 44 52 55 552 563 666 672 683 772 834 922 2223 2456 3333 3423 33...
^ ^- -^ ^^ -- ^^ ^^- --- ^^^ ^-- --- ^^- --- -^^ ^^^- ---- ^^^^ ^--
.2..2...3...2...4....4.....4....5.....2...5......5.....5......5...2....
.=..#...=...#...=....#.....=....#.....=...#......=.....#......=...#
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Eric Angelini, May 05 2005
STATUS
approved