A121969 Numbers k such that if you subtract k-reversed from k you get a natural number with the same digits as k.

954, 1980, 2961, 3870, 5823, 7641, 9108, 19980, 29880, 29961, 32760, 38970, 39780, 49680, 49842, 54270, 58923, 59580, 60273, 60732, 69462, 69480, 69723, 70254, 73260, 76941, 79344, 79380, 89226, 89280, 89604, 90810, 91908, 96732, 99108

Offset: 1

Author

Tanya Khovanova, Sep 04 2006

Keywords

• base
• nonn
• changed

Examples

			954 - 459 = 495, 19980 - 8991 = 10989.
		

References

• David Wells, The Penguin Dictionary of Curious and Interesting Numbers (Rev. ed. 1997), p. 154 (entry for 1980).

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A055161.

Programs

Mathematica

srdQ[n_]:=Module[{idn=IntegerDigits[n],rn},rn=FromDigits[Reverse[idn]];n>rn&&Sort[IntegerDigits[n-rn]]==Sort[idn]]; Select[Range[100000], srdQ] (* Harvey P. Dale, Jun 21 2013 *)

PARI

isok(n) = {my(d = digits(n)); diff = my(n - subst(Polrev(d), x, 10)); (diff > 0) && (vecsort(digits(diff)) == vecsort(d));} \\ Michel Marcus, Sep 04 2015