OFFSET
1,2
COMMENTS
From the second row onward, the fixed point is 2.
First differs from A325239 at row n = 8.
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..10000 (rows 1..2292 of triangle, flattened).
EXAMPLE
Triangle begins:
1;
2;
3, 2;
4, 3, 2;
5, 2;
6, 4, 3, 2;
7, 2;
8, 4, 3, 2;
9, 3, 2;
10, 4, 3, 2;
11, 2;
12, 6, 4, 3, 2;
...
MATHEMATICA
Array[Most[FixedPointList[DivisorSigma[0, #] &, #]] &, 30]
PROG
(PARI) row(n) = if (n==1, [1], my(list=List()); listput(list, n); while (n != 2, n = numdiv(n); listput(list, n)); Vec(list)); \\ Michel Marcus, Aug 21 2024
CROSSREFS
KEYWORD
nonn,tabf,easy
AUTHOR
Paolo Xausa, Aug 18 2024
STATUS
approved