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A230356 Nonsquare numbers n such that digit sum of n = digit sum of square part of n. 3
10, 18, 27, 40, 45, 54, 63, 72, 90, 108, 117, 126, 135, 153, 160, 162, 171, 180, 207, 216, 220, 234, 243, 250, 252, 261, 270, 304, 306, 315, 333, 342, 351, 360, 405, 414, 423, 432, 450, 490, 504, 513, 522, 531, 540, 603, 612, 621, 630, 640, 702, 711, 720, 801, 810, 931 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

135 = 2^3*5. Square part of 135 is 9. Digit_sum(135) =9, digit_sum(9) = 9.

PROG

(PARI)

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=n/core(n); if(digsum(n)==digsum(m)&&m<>n, print(n))); }

CROSSREFS

Cf. A006753, A230354, A230355, A230357.

Sequence in context: A257512 A125689 A244573 * A100992 A256382 A167607

Adjacent sequences:  A230353 A230354 A230355 * A230357 A230358 A230359

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.