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A342766
a(1) = 1, for any n > 1, a(n) = A342765(a(n-1), n).
2
1, 2, 3, 6, 10, 10, 14, 28, 42, 42, 66, 66, 78, 78, 78, 156, 204, 204, 228, 228, 228, 228, 276, 276, 460, 460, 690, 690, 870, 870, 930, 1860, 1860, 1860, 1860, 1860, 2220, 2220, 2220, 2220, 2460, 2460, 2580, 2580, 2580, 2580, 2820, 2820, 3948, 3948, 3948, 3948
OFFSET
1,2
COMMENTS
This sequence has similarities with A087052.
This sequence is nondecreasing.
A new value is introduced at each power of prime (A000961).
The ordinal transform of the sequence is A276781.
The RUNS transform of the sequence is A057820.
EXAMPLE
The first terms, alongside their prime factorizations, are:
n a(n) n a(n)
-- ---- --------- ----------
1 1 1 1
2 2 2 2
3 3 3 3
4 6 2 * 2 2 * 3
5 10 5 2 * 5
6 10 2 * 3 2 * 5
7 14 7 2 * 7
8 28 2 * 2 * 2 2 * 2 * 7
9 42 3 * 3 2 * 3 * 7
10 42 2 * 5 2 * 3 * 7
11 66 11 2 * 3 * 11
12 66 2 * 2 * 3 2 * 3 * 11
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, Apr 02 2021
STATUS
approved