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A344979
Numbers k such that A011772(k) is equal to A344878(k).
3
1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 19, 21, 23, 25, 26, 27, 29, 31, 32, 37, 39, 41, 43, 47, 49, 50, 53, 57, 59, 61, 64, 67, 71, 73, 74, 75, 78, 79, 81, 83, 89, 93, 97, 98, 101, 103, 107, 109, 111, 113, 121, 122, 125, 127, 128, 129, 131, 137, 139, 146, 147, 149, 150, 151, 157, 163, 167, 169, 173, 179, 181, 183, 191, 193, 194
OFFSET
1,2
PROG
(PARI)
A011772(n) = { if(n==1, return(1)); my(f=factor(if(n%2, n, 2*n)), step=vecmax(vector(#f~, i, f[i, 1]^f[i, 2]))); forstep(m=step, 2*n, step, if(m*(m-1)/2%n==0, return(m-1)); if(m*(m+1)/2%n==0, return(m))); }; \\ From A011772
A344878(n) = if(1==n, n, my(f=factor(n)~); lcm(vector(#f, i, (f[1, i]^(f[2, i]+(2==f[1, i]))-1))));
isA344979(n) = (A344878(n)==A011772(n));
CROSSREFS
Cf. A011772, A344878, A344885 (characteristic function).
Positions of zeros in A344976.
Union of A000961 and A344978. Subsequence of A344974.
Sequence in context: A119314 A317923 A371058 * A273130 A273200 A360117
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 05 2021
STATUS
approved