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A165550 Sum of digits of square is sum of square of digits. 3
0, 1, 2, 3, 10, 20, 30, 33, 100, 200, 300, 330, 333, 1000, 1143, 1431, 2000, 2242, 3000, 3233, 3300, 3330, 3331, 3333, 3411, 3433, 4131, 10000, 11234, 11243, 11344, 11403, 11430, 11432, 11433, 12235, 12523, 13134, 13142, 13144, 13241, 13431, 13522 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

EXAMPLE

Consider n=33: n^2 is 1089, sum of square of digits is 3^2+3^2=18, and sum of digits of square is 1+0+8+9=18, thus 33 appears in the sequence.

PROG

(PARI) digsum(n) = my(s=0); while(n, s=s+n%10; n=n\10); s;

sqadigsum(n) = my(s=0); while(n, s=s+(n%10)^2; n=n\10); s;

for(n=0, 100000, if(sqadigsum(n)==digsum(n^2), print1(n, ", ") ) )

CROSSREFS

Sequence in context: A295951 A083944 A306106 * A328780 A184261 A095919

Adjacent sequences:  A165547 A165548 A165549 * A165551 A165552 A165553

KEYWORD

base,easy,nonn

AUTHOR

Rémy Sigrist, Sep 21 2009

EXTENSIONS

Offset fixed by Rémy Sigrist, Feb 03 2017

STATUS

approved

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Last modified October 22 18:45 EDT 2021. Contains 348175 sequences. (Running on oeis4.)