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A164776
Numbers n with property that average digit of n^2 is s=4.
10
2, 41, 58, 59, 68, 85, 95, 1027, 1034, 1036, 1072, 1081, 1088, 1108, 1124, 1135, 1144, 1153, 1169, 1232, 1234, 1243, 1252, 1259, 1268, 1277, 1279, 1295, 1297, 1306, 1315, 1331, 1340, 1342, 1349, 1358, 1360, 1369, 1385, 1394, 1405, 1423, 1441, 1448, 1457
OFFSET
1,1
EXAMPLE
41^2 = 1681 and (1 + 6 + 8 + 1)/4 = 4
58^2 = 3364 and (3 + 3 + 6 + 4)/4 = 4.
PROG
(PARI) dsum(n)={my(s=0); while(n>9, s+=n%10; n\=10); s+n};
for(n=1, 1e6, if(dsum(n^2)/#Str(n^2)==4, print1(n", "))) \\ Charles R Greathouse IV, Nov 01 2009
CROSSREFS
Subsequence of A164817.
Average of digits of n^2 = s: A164771 (s=1), A164770 (s=2), A164782 (s=3), A164776 (s=4), A164774 (s=5), A164778 (s=6), A164773 (s=7), A164772 (s=8).
Sequence in context: A059698 A107190 A215391 * A158084 A243990 A141858
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Aug 26 2009
STATUS
approved