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A324118
Sum of odd divisors in A156552(n): a(1) = 0, for n > 1, a(n) = A000593(A156552(n)) = A000203(A322993(n)).
6
0, 1, 1, 4, 1, 6, 1, 8, 4, 13, 1, 12, 1, 18, 6, 24, 1, 14, 1, 20, 13, 48, 1, 24, 4, 84, 8, 48, 1, 32, 1, 32, 18, 176, 6, 40, 1, 258, 48, 56, 1, 38, 1, 68, 12, 800, 1, 48, 4, 31, 84, 132, 1, 30, 13, 72, 176, 1302, 1, 44, 1, 2736, 20, 104, 18, 96, 1, 304, 258, 42, 1, 72, 1, 4356, 14, 624, 6, 160, 1, 80, 24, 10928, 1, 124, 48, 20520, 800, 240, 1, 78, 13
OFFSET
1,4
FORMULA
a(1) = 0; for n > 1, a(n) = A000593(A156552(n)) = A000203(A322993(n)) = A323243(2*A246277(n)).
PROG
(PARI)
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A246277(n) = { if(1==n, 0, while((n%2), n = A064989(n)); (n/2)); };
A322993(n) = A156552(2*A246277(n));
A324118(n) = if(1==n, 0, sigma(A322993(n)));
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 20 2019
STATUS
approved