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A318939
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If n=0 then 1 otherwise 48*(1+12*A318935(n))*(sum of cubes of odd divisors of n).
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1
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1, 624, 5232, 17472, 42096, 78624, 146496, 214656, 337008, 472368, 659232, 831168, 1178688, 1371552, 1799808, 2201472, 2696304, 3066336, 3960624, 4280640, 5304096, 6010368, 6969024, 7592832, 9436224, 9828624, 11499936, 12754560, 14481024
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OFFSET
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0,2
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LINKS
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MAPLE
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with(numtheory);
T:= n -> add(2^(3*m), m=0..A007814(n));
f := proc(n) local t2, i, d;
if n=0 then return(1); fi;
t2:=0; for d in divisors(n) do if (d mod 2) = 1 then t2:=t2+d^3; fi; od:
48*(1+12*T(n))*t2;
end;
[seq(f(n), n=0..50)];
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PROG
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(Python)
from sympy import divisor_sigma
def A318939(n): return 3*(1+12*((1<<(3*(m:=(~n&n-1).bit_length())+3))-1)//7)*divisor_sigma(n>>m, 3)<<4 if n else 1 # Chai Wah Wu, Jul 11 2022
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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