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A140645
Digit sums of highly composite numbers.
2
1, 2, 4, 6, 3, 6, 9, 12, 6, 3, 9, 6, 9, 9, 12, 9, 15, 9, 9, 18, 9, 9, 9, 9, 18, 18, 9, 18, 18, 18, 18, 18, 18, 18, 36, 18, 27, 18, 18, 18, 18
OFFSET
1,2
COMMENTS
Except for the first three terms, all others are multiples of 3.
FORMULA
a(n) = A007953(A002182(n)). - Amiram Eldar, Nov 13 2019
EXAMPLE
2162160 is a highly composite number whose digit sum is 18.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Jul 08 2008
STATUS
approved