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

1,1

LINKS

Table of n, a(n) for n=1..58.

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

Cf. A006753, A219340, A230355, A230356, A230357.

Sequence in context: A277725 A079479 A162694 * A197464 A124205 A133403

Adjacent sequences:  A230351 A230352 A230353 * A230355 A230356 A230357

KEYWORD

nonn,base,less

AUTHOR

Antonio Roldán, Oct 16 2013

STATUS

approved

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Last modified July 25 04:48 EDT 2017. Contains 289779 sequences.