OFFSET
1,1
COMMENTS
These numbers are called antipalindromic in base 10 by Dvorakova et al. - Michel Marcus, Aug 18 2020
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..9999
Lubomira Dvorakova, Stanislav Kruml, and David Ryzak, Antipalindromic numbers, arXiv:2008.06864 [math.CO], 2020.
EXAMPLE
1278 is a term of the sequence because its complement in base 10 is 8721 and the digit reversal is again 1278.
MAPLE
P:=proc(q, h) local a, b, k, n; for n from 1 to q do a:=convert(n, base, h); b:=0;
for k from 1 to nops(a) do a[k]:=h-1-a[k]; b:=h*b+a[k]; od; if b=n then print(n); fi; od; end: P(10^2, 10);
PROG
(PARI) isok(m) = {my(d=digits(m)); for (j=1, #d, if (d[j] + d[#d+1-j] != 9, return(0)); ); return (1); } \\ Michel Marcus, Aug 18 2020
(PARI) a(n) = my (d=digits(n)); n*10^#d + fromdigits(apply (t -> 9-t, Vecrev(d))) \\ Rémy Sigrist, Aug 18 2020
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Paolo P. Lava, Apr 05 2017
STATUS
approved