A378481 Integers k such that A378414(k) == k (mod A066417(k)).
33, 77, 153, 372, 1540, 2300, 2692, 2736, 7812, 8721, 12593, 26025, 26481, 27972, 39321, 64009, 104409, 175441, 325180, 335616, 422593, 455625, 564376, 575040, 756460, 800073, 1104521, 2180545, 2304332, 3502665, 3691968, 5130909, 5515121, 9331441, 9546265
Offset: 1
Examples
Antidivisors of 77 are 2, 3, 5, 9, 14, 17, 22, 31, 51 and their sum is 154. Then 77*78/2 mod 154 = 3003 mod 154 = 77.
Programs
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Maple
with(numtheory): P:=proc(q) local j,k,n,v; v:=[]; for n from 3 to q do k:=0; j:=n; while j mod 2<>1 do k:=k+1; j:=j/2; od; if n*(n+1)/2 mod (sigma(2*n+1)+sigma(2*n-1)+sigma(n/2^k)*2^(k+1)-6*n-2)=n then v:=[op(v),n]; fi; od; op(v); end: P(10^5);
Comments