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A230357 Numbers n such that digit sum of n equals digit sum of sopf(n) (sum of the distinct prime factors of n). 3
22, 94, 105, 114, 136, 140, 160, 166, 202, 222, 234, 250, 265, 274, 346, 355, 361, 382, 424, 438, 445, 454, 516, 517, 526, 532, 562, 634, 702, 706, 712, 732, 812, 913, 915, 922, 1036, 1071, 1086, 1111, 1116, 1122, 1138, 1165, 1185, 1204, 1206, 1219, 1221, 1230, 1239, 1255, 1282, 1312, 1316, 1318, 1345, 1363, 1400, 1404, 1432, 1507, 1520, 1530, 1550 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..65.

EXAMPLE

166=2*83. Sopf(166)=85. Digit_sum(166)=13, digit_sum(85)=13.

PROG

(PARI)

sopf(n)= { local(f, s=0); f=factor(n); for(i=1, matsize(f)[1], s+=f[i, 1]); return(s) }

digsum(n)={local (d, p); d=0; p=n; while(p, d+=p%10; p=floor(p/10)); return(d)}

{for (n=4, 2*10^3, m=sopf(n); if(digsum(n)==digsum(m)&&m<>n, print(n)))}

CROSSREFS

Cf. A006753,  A036920, A230354, A230355, A230356.

Sequence in context: A041942 A231265 A041944 * A145769 A256152 A159539

Adjacent sequences:  A230354 A230355 A230356 * A230358 A230359 A230360

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.