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 A085445 Numbers equal to exactly twice the sum of the products of each of their digits. 1
 0, 50, 162, 392, 648 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 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 n again. Actually, the "sum of the products of the digits" is simply the square of the sum of digits. Sequence is complete. - Giovanni Resta, Mar 21 2013 LINKS EXAMPLE 162 = 2*(1*1 + 1*6 + 1*2 + 6*1 + 6*6 + 6*2 + 2*1 + 2*6 + 2*2). CROSSREFS Cf. A085444. Sequence in context: A044763 A165676 A160783 * A048511 A206128 A333101 Adjacent sequences:  A085442 A085443 A085444 * A085446 A085447 A085448 KEYWORD base,fini,full,nonn AUTHOR Chuck Seggelin (barkeep(AT)plastereddragon.com), Jun 30 2003 STATUS approved

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Last modified September 19 02:20 EDT 2021. Contains 347550 sequences. (Running on oeis4.)