OFFSET
1,5
COMMENTS
Any positive integer appears infinitely many times.
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..26796
EXAMPLE
The sequence begins: 0, 1, 1, 1, 2, 1, 1, 2, 2, 1, ...
It represents a rectangular array read by downward antidiagonals. The first row of the array is this sequence itself; so is the first column. Every term in the array is the sum of the initial terms of its row and column:
0 1 1 1 2 1...
1 2 2 2 3...
1 2 2 2...
1 2 2...
2 3...
1...
...
MATHEMATICA
Nest[Flatten@Table[#[[n - i]] + #[[i]], {n, Length[#] + 1}, {i, n - 1}] &, {0, 1}, 4]
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Ivan Neretin, Mar 14 2017
STATUS
approved