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A324110
Numbers k such that A324108(k) != A324054(k-1).
6
15, 21, 30, 33, 35, 39, 42, 45, 51, 55, 57, 60, 63, 65, 66, 69, 70, 75, 77, 78, 84, 85, 90, 91, 93, 95, 99, 102, 105, 110, 111, 114, 115, 117, 119, 120, 123, 126, 129, 130, 132, 133, 135, 138, 140, 141, 143, 145, 147, 150, 153, 154, 155, 156, 159, 161, 165, 168, 170, 171, 175, 177, 180, 182, 183, 185, 186, 187, 189, 190, 195, 198, 201
OFFSET
1,1
COMMENTS
This is a subsequence of A070537. The missing terms 1, 87, 174, 348, 696, 1392, 2091, ..., are at A324111.
LINKS
PROG
(PARI)
A324054(n) = { my(p=2, mp=p*p, m=1); while(n, if(!(n%2), p=nextprime(1+p); mp = p*p, if(3==(n%4), mp *= p, m *= (mp-1)/(p-1))); n>>=1); (m); };
A324108(n) = { my(f=factor(n)); prod(i=1, #f~, A324054((f[i, 1]^f[i, 2])-1)); };
isA324110(n) = (A324054(n-1)!=A324108(n));
for(n=1, 201, if(isA324110(n), print1(n, ", ")))
CROSSREFS
Cf. A070537, A324054, A324108, A324109 (complement), A324111.
Sequence in context: A195527 A047200 A070537 * A285800 A340380 A184041
KEYWORD
nonn
AUTHOR
STATUS
approved