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A378521
Möbius transform of A048673.
1
1, 1, 2, 3, 3, 4, 5, 9, 10, 6, 6, 12, 8, 10, 12, 27, 9, 20, 11, 18, 20, 12, 14, 36, 21, 16, 50, 30, 15, 24, 18, 81, 24, 18, 30, 60, 20, 22, 32, 54, 21, 40, 23, 36, 60, 28, 26, 108, 55, 42, 36, 48, 29, 100, 36, 90, 44, 30, 30, 72, 33, 36, 100, 243, 48, 48, 35, 54, 56, 60, 36, 180, 39, 40, 84, 66, 60, 64, 41, 162, 250
OFFSET
1,3
FORMULA
a(n) = Sum_{d|n} A008683(n/d)*A048673(d).
a(n) = A072451(A048673(n)).
a(n) = A055034(A003961(n)) = A349136(A003961(n)).
For n > 1, a(n) = A003972(n)/2 = A000010(A003961(n))/2.
PROG
(PARI)
A048673(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); (factorback(f)+1)/2; };
A378521(n) = sumdiv(n, d, moebius(n/d)*A048673(d));
(PARI)
A003961(n) = { my(f=factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A378521(n) = if(1==n, n, eulerphi(A003961(n))/2);
KEYWORD
nonn,new
AUTHOR
Antti Karttunen, Nov 30 2024
STATUS
approved