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

1,1

Comments

These are the resulting strings in A339403.

Links

Table of n, a(n) for n=1..50.

Example

204 = 6*34 contains reverse(6+34) = reverse(40) = 04 as a substring, so 204 is a term.

Mathematica

q[n_] := AnyTrue[Divisors[n], SequenceCount[IntegerDigits[n], Reverse @ IntegerDigits[# + n/#]] > 0 &]; Select[Range[2000], q] (* Amiram Eldar, Jan 26 2021 *)

Prog

(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)); ); }

Crossrefs

Cf. A339403, A340916.

Sequence in context: A262235 A133003 A358293 * A161791 A132097 A128062

Adjacent sequences: A340914 A340915 A340916 * A340918 A340919 A340920

Keyword

nonn,base

Author

Michel Marcus, Jan 26 2021

Status

approved