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A376257
a(n) = (n - c(n))*(-1)^c(n), where c(n) is the product of the digits of n (A007954).
0
0, 0, 0, 0, 0, 0, 0, 0, 0, 10, -10, 10, -10, 10, -10, 10, -10, 10, -10, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 30, -28, 26, -24, 22, -20, 18, -16, 14, -12, 40, 37, 34, 31, 28, 25, 22, 19, 16, 13, 50, -46, 42, -38, 34, -30, 26, -22, 18, -14, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 70, -64, 58
OFFSET
1,10
COMMENTS
There is an interesting pattern on the graph of the sequence.
FORMULA
a(n) = (n-A007954(n)) * (-1)^A007954(n).
EXAMPLE
For n = 129: 1*2*9=18. So a(n) = (129-18)*(-1)^18 = 111.
CROSSREFS
Sequence in context: A109751 A160941 A070565 * A169932 A245403 A091837
KEYWORD
sign,base,look
AUTHOR
Stuart Coe, Sep 17 2024
STATUS
approved