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Search: a354812 -id:a354812
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Dirichlet inverse of A324198, where A324198(n) = gcd(n, A276086(n)).
+10
20
1, -1, -3, 0, -1, 5, -1, 0, 6, -3, -1, -2, -1, 1, -9, 0, -1, -16, -1, 4, 3, 1, -1, 0, -24, 1, -12, 0, -1, 43, -1, 0, 3, 1, -5, 14, -1, 1, 3, 0, -1, -11, -1, 0, 54, 1, -1, 0, -6, 32, 3, 0, -1, 44, -3, -6, 3, 1, -1, -50, -1, 1, -24, 0, 1, -5, -1, 0, 3, -15, -1, -4, -1, 1, 96, 0, -5, -5, -1, 0, 24, 1, -1, 8, -3, 1, 3, 0, -1
OFFSET
1,3
FORMULA
a(n) = A346243(n) - A324198(n).
From Antti Karttunen, Jun 09 2022: (Start)
a(1) = 1, and for n > 1, a(n) = -Sum_{d|n, d<n} A324198(n/d) * a(d).
For all n >= 1, A000035(a(n)) = A008966(n).
For all n >= 1, a(A045344(n)) = -1.
(End)
PROG
(PARI)
up_to = 65537;
DirInverseCorrect(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = (-u[1]*sumdiv(n, d, if(d<n, v[n/d]*u[d], 0)))); (u) }; \\ Compute the Dirichlet inverse of the sequence given in input vector v.
A324198(n) = { my(m=1, p=2, orgn=n); while(n, m *= (p^min(n%p, valuation(orgn, p))); n = n\p; p = nextprime(1+p)); (m); };
v346242 = DirInverseCorrect(vector(up_to, n, A324198(n)));
A346242(n) = v346242[n];
CROSSREFS
Cf. A008966 (parity of terms), A005117 (positions of odd terms), A013929 (of even terms), A045344 (of -1's, at least a subset of them), A354810 (of 0's), A354811 (of 1's), A354812 (of 2's), A354813 (of 3's), A354814 (of 4's), A354822 (of -2's).
KEYWORD
sign,base
AUTHOR
Antti Karttunen, Jul 13 2021
STATUS
approved
Positions of zeros in A346242.
+10
3
4, 8, 16, 24, 28, 32, 40, 44, 48, 52, 64, 68, 76, 80, 88, 92, 96, 104, 116, 121, 124, 128, 136, 144, 148, 152, 160, 164, 169, 172, 176, 184, 188, 192, 208, 212, 232, 236, 240, 244, 248, 256, 268, 272, 284, 288, 289, 292, 296, 304, 312, 316, 320, 328, 332, 338, 344, 356, 361, 364, 368, 376, 384, 388, 404, 408, 412, 416
OFFSET
1,1
PROG
(PARI) isA354810(n) = (0==A346242(n));
CROSSREFS
Cf. A346242, A354820 (characteristic function).
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 07 2022
STATUS
approved
Positions of -2's in A346242.
+10
3
12, 1092, 1596, 2436, 3108, 3612, 3876, 4692, 4884, 4956, 5244, 5628, 5916, 6132, 6324, 6612, 6636, 7068, 7476, 7548, 8004, 8148, 8364, 8436, 8556, 8652, 8772, 9156, 9348, 9588, 9804, 10212, 10668, 10716, 10788, 10812, 11316, 11676, 11868, 12036, 12084, 12444, 12516, 12876, 12972, 13188, 13452, 13668, 13692, 13764
OFFSET
1,1
COMMENTS
Question: Are all terms even?
PROG
(PARI) isA354822(n) = (-2==A346242(n));
CROSSREFS
Cf. A346242.
Cf. also A354812.
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 07 2022
STATUS
approved

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