OFFSET
1,1
FORMULA
The function digit-mult(n) multiplies all digits d of n, where d > 0. For example, digit-mult(1230) = 1 * 2 * 3 = 6. Therefore, in base 17, digit-mult(digit-sum(9999)) = digit-mult(22) = 2 * 2 = 4 (22 in base 17 = 36 in base 10).
EXAMPLE
105701 = digit-mult(digit-sum(2)) + digit-mult(digit-sum(3)) + ... digit-mult(digit-sum(148CC)) = digit-mult(2) + digit-mult(3) + ... digit-mult(23) = 2 + 3 + ... 2*3. Note that 148CC and 23 in base 17 = 105701 and 37 in base 10.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Anthony Sand, May 16 2014
STATUS
approved