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A109709
Triangle in which n-th row gives the prime factors of the n-th composite number with repetition.
0
2, 2, 2, 3, 2, 2, 2, 3, 3, 2, 5, 2, 2, 3, 2, 7, 3, 5, 2, 2, 2, 2, 2, 3, 3, 2, 2, 5, 3, 7, 2, 11, 2, 2, 2, 3, 5, 5, 2, 13, 3, 3, 3, 2, 2, 7, 2, 3, 5, 2, 2, 2, 2, 2, 3, 11, 2, 17, 5, 7, 2, 2, 3, 3, 2, 19, 3, 13, 2, 2, 2, 5, 2, 3, 7, 2, 2, 11, 3, 3, 5, 2, 23, 2, 2, 2, 2, 3, 7, 7, 2, 5, 5, 3, 17, 2, 2, 13, 2, 3, 3, 3
OFFSET
1,1
EXAMPLE
Irregular triangle begins:
2, 2;
2, 3;
2, 2, 2;
3, 3;
2, 5;
...
MATHEMATICA
fn[{a_, b_}]:=Table[a, b]; Flatten[Table[fn/@FactorInteger[ ResourceFunction["Composite"][n]], {n, 37}]] (* James C. McMahon, Mar 29 2024 *)
CROSSREFS
Column k=1 gives A056608.
Last terms in rows give A052369.
Row lengths give A062502(n+1).
Sequence in context: A065569 A262941 A127656 * A125604 A216685 A331853
KEYWORD
nonn,tabf
AUTHOR
Lior Manor, Aug 08 2005
STATUS
approved