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A230354
Even numbers n such that digit sum of n = digit sum of largest odd divisor of n.
3
12, 18, 36, 54, 60, 72, 90, 108, 126, 132, 144, 156, 162, 180, 198, 204, 216, 228, 234, 240, 252, 270, 276, 306, 320, 324, 342, 348, 360, 372, 378, 396, 414, 420, 432, 450, 504, 516, 522, 540, 558, 594, 612, 624, 630, 636, 660, 702, 708, 720, 732, 738, 756, 774, 780, 792, 810, 900
OFFSET
1,1
EXAMPLE
Largest odd divisor of 162 is 81. Digit_sum(162)=9, digit_sum(81)=9
PROG
(PARI)
mdi(n)= n / 2^valuation(n, 2)
digsum(n)={local (d, p); d=0; p=n; while(p, d+=p%10; p=floor(p/10)); return(d)}
{for (n=2, 10^3, m=mdi(n); if(digsum(n)==digsum(mdi(n))&&m<>n, print(n))); }
CROSSREFS
KEYWORD
nonn,base,less
AUTHOR
Antonio Roldán, Oct 16 2013
STATUS
approved