A121969 - OEIS

A121969

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

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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

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

EXAMPLE

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

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 *)

PROG

(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

CROSSREFS

Cf. A055161.

Sequence in context: A048267 A251677 A073500 * A203024 A055161 A055158

Adjacent sequences: A121966 A121967 A121968 * A121970 A121971 A121972

KEYWORD

base,nonn

AUTHOR

Tanya Khovanova, Sep 04 2006

STATUS

approved