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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 (list; graph; refs; listen; history; text; internal format)
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

Harvey P. Dale, Table of n, a(n) for n = 0..1000

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: A259220 A107120 A045010 * A274027 A206210 A044985

Adjacent sequences:  A085443 A085444 A085445 * A085447 A085448 A085449

KEYWORD

base,nonn

AUTHOR

Chuck Seggelin (barkeep(AT)plastereddragon.com), Jun 30 2003

STATUS

approved

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Last modified November 22 08:46 EST 2019. Contains 329389 sequences. (Running on oeis4.)