A344979 Numbers k such that A011772(k) is equal to A344878(k).

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

Links

Table of n, a(n) for n=1..77.

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

Adjacent sequences: A344976 A344977 A344978 * A344980 A344981 A344982

Keyword

nonn

Author

Antti Karttunen, Jun 05 2021

Status

approved