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A333034
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a(n) is the sum of the digits of the squares of all n-digit numbers.
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2
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69, 1410, 21921, 298725, 3792660, 46016727, 541129686, 6221175405, 70311424443, 784112741880, 8651123311875, 94611219470547
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 1+4+9+(1+6)+(2+5)+(3+6)+(4+9)+(6+4)+(8+1) = 69.
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MAPLE
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ds:= proc(x) local t, s, r;
s:= x; t:= 0;
while s > 0 do
r:= s mod 10;
t:= t + r;
s:= (s-r)/10;
od;
t
end proc:
seq(add(ds(x^2), x=10^(n-1)..10^n-1), n=1..5);
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PROG
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(PARI) for(d=0, 6, print1(sum(k=10^d, 10^(d+1)-1, vecsum(digits(k^2))), ", ")) \\ Hugo Pfoertner, Mar 05 2020
(Python)
return sum(int(d) for i in range(10**(n-1), 10**n) for d in str(i**2)) # Chai Wah Wu, Mar 05 2020
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CROSSREFS
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KEYWORD
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nonn,more,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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