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A350380
Triangle read by rows in which row n lists A014963(d), the exponential of Mangoldt function, for each divisor d of n.
1
1, 1, 2, 1, 3, 1, 2, 2, 1, 5, 1, 2, 3, 1, 1, 7, 1, 2, 2, 2, 1, 3, 3, 1, 2, 5, 1, 1, 11, 1, 2, 3, 2, 1, 1, 1, 13, 1, 2, 7, 1, 1, 3, 5, 1, 1, 2, 2, 2, 2, 1, 17, 1, 2, 3, 1, 3, 1, 1, 19, 1, 2, 2, 5, 1, 1, 1, 3, 7, 1, 1, 2, 11, 1, 1, 23, 1, 2, 3, 2, 1, 2, 1, 1, 1, 5, 5, 1, 2, 13, 1
OFFSET
1,3
LINKS
Michel Marcus, Table of n, a(n) for n = 1..10006 (rows 1 to 1358, flattened).
FORMULA
a(n) = A014963(A027750(n)).
EXAMPLE
Triangle begins:
1;
1, 2;
1, 3;
1, 2, 2;
1, 5;
1, 2, 3, 1;
1, 7;
1, 2, 2, 2;
1, 3, 3;
1, 2, 5, 1;
...
MATHEMATICA
Table[Exp[MangoldtLambda[Divisors[n]]], {n, 1, 26}] // Flatten (* Amiram Eldar, Dec 28 2021 *)
PROG
(PARI) M(n) = ispower(n, , &n); if(isprime(n), n, 1); \\ A014963
row(n) = apply(M, divisors(n));
CROSSREFS
Cf. A000027 (row products), A140255 (row sums).
Sequence in context: A317656 A319136 A320777 * A069929 A304081 A101312
KEYWORD
nonn,tabf
AUTHOR
Michel Marcus, Dec 28 2021, following a suggestion from Charles Kusniec
STATUS
approved