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A324052
a(n) = A083254(A005940(1+n)).
8
1, 0, 1, 0, 3, -2, 3, 0, 5, -2, 1, -4, 15, -6, 9, 0, 9, -2, 3, -4, 13, -14, 3, -8, 35, -10, 5, -12, 75, -18, 27, 0, 11, -2, 7, -4, 25, -18, 9, -8, 43, -22, -9, -28, 65, -42, 9, -16, 99, -14, 21, -20, 91, -70, 15, -24, 245, -50, 25, -36, 375, -54, 81, 0, 15, -2, 9, -4, 31, -26, 21, -8, 53, -30, -5, -36, 125, -54, 27, -16, 97, -34, 9
OFFSET
0,5
FORMULA
a(n) = A083254(A005940(1+n)).
a(n) = 2*A290077(n) - A005940(1+n).
For n >= 1, a(n) = A324182(A054429(n)).
For n >= 1, a((2^n)-1) = 0.
PROG
(PARI) A324052(n) = { my(m1=1, m2=2, p=2); while(n, if(!(n%2), p=nextprime(1+p), m1 *= p; m2 *= (p-(1==(n%4)))); n>>=1); (m2-m1); };
(PARI)
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
A083254(n) = (2*eulerphi(n)-n);
A324052(n) = A083254(A005940(1+n));
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 18 2019
STATUS
approved