A345945 Numbers k that have such a proper divisor d for which A002034(d) = A002034(k).

6, 8, 10, 12, 14, 15, 18, 20, 21, 22, 24, 26, 28, 30, 33, 34, 35, 36, 38, 39, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 112, 114, 115, 116, 117

Offset: 1

Author

Antti Karttunen, Jul 04 2021

Keywords

• nonn

Examples

			21 = 3*7 is present because A002034(21) = 7 = A002034(7).
		

Links

• Index entries for sequences related to factorial numbers

Crossrefs

Cf. A002034, A345944 (complement).

Positions of terms > 1 in A345935.

Union of A024619 and A345946.

Cf. also A344882.

Programs

PARI

A002034(n) = if(1==n,n,my(s=factor(n)[, 1], k=s[#s], f=Mod(k!, n)); while(f, f*=k++); (k)); \\ After code in A002034.
A345950(n) = { my(x=A002034(n)); fordiv(n,d,if(A002034(d)==x,return(d==n))); };
isA345945(n) = !A345950(n);