login
A085446
Numbers divisible by twice the sum of the products of each of their digits, excluding even multiples of 10.
2
162, 324, 392, 512, 648, 1134, 1296, 1944, 2106, 2592, 2704, 3402, 4212, 4536, 5022, 5184, 5632, 5832, 7128, 7514, 7744, 8424, 8748, 9072, 10044, 10206, 10368, 10406, 11016, 11502, 11664, 12032, 12312, 12716, 13122, 13608, 14256, 14504, 14904
OFFSET
0,1
COMMENTS
Take a number n, create a table with d columns and rows where d=number of digits of n. Each column corresponds to a digit of n and each row to a digit of n. In each cell, multiply the two digits of n represented by that row and column. Add up the sums of all of the rows and all of the columns to get a new number m which divides n.
LINKS
EXAMPLE
512 / (2*(5*5 + 5*1 + 5*2 + 1*5 + 1*1 + 1*2 + 2*5 + 2*1 + 2*2)) = 4.
MATHEMATICA
Select[Range[15000], !Divisible[#, 10]&&Divisible[#, 2Total[Times @@@ Tuples[ IntegerDigits[#], 2]]]&] (* Harvey P. Dale, Aug 19 2014 *)
CROSSREFS
Cf. A085444.
Sequence in context: A045010 A372972 A373737 * A274027 A206210 A044985
KEYWORD
base,nonn
AUTHOR
Chuck Seggelin (barkeep(AT)plastereddragon.com), Jun 30 2003
STATUS
approved