A340917 Integers m that have at least one divisor d such that reverse(d+m/d) is a substring of m.
4, 72, 81, 94, 114, 130, 132, 148, 168, 204, 231, 236, 245, 272, 294, 414, 448, 456, 498, 518, 585, 594, 756, 792, 836, 867, 936, 988, 994, 1056, 1127, 1170, 1210, 1221, 1271, 1281, 1380, 1478, 1608, 1680, 1748, 1768, 1782, 1798, 1887, 1914, 1930, 1938, 1948, 1960
Offset: 1
Examples
204 = 6*34 contains reverse(6+34) = reverse(40) = 04 as a substring, so 204 is a term.
Programs
-
Mathematica
q[n_] := AnyTrue[Divisors[n], SequenceCount[IntegerDigits[n], Reverse @ IntegerDigits[# + n/#]] > 0 &]; Select[Range[2000], q] (* Amiram Eldar, Jan 26 2021 *)
-
PARI
isok(n) = {fordiv(n, d, if (#strsplit(Str(n), concat(Vecrev(Str(d+n/d)))) > 1, return(1)); if (d^2 > n, return(0)););}
Comments