A265558 - OEIS

%I #10 Jun 24 2022 14:07:12

%S 0,1,2,3,4,5,6,7,8,9,11,11,22,33,44,55,66,77,88,99,22,22,22,33,44,55,

%T 66,77,88,99,33,33,33,33,44,55,66,77,88,99,44,44,44,44,44,55,66,77,88,

%U 99,55,55,55,55,55,55,66,77,88,99,66,66,66,66,66,66,66,77,88,99,77,77,77,77,77,77,77,77,88,99,88,88

%N a(n) = smallest base-10 palindrome m >= n such that every base-10 digit of n is <= the corresponding digit of m.

%H Rémy Sigrist, <a href="/A265558/b265558.txt">Table of n, a(n) for n = 0..10000</a>

%p For Maple code see A265543.

%o (PARI) a(n,base=10) = { my (d=digits(n,base)); for (k=1, #d\2, d[k]=d[#d+1-k]=max(d[k],d[#d+1-k])); fromdigits(d,base) } \\ _Rémy Sigrist_, Jun 24 2022

%Y Sequences related to palindromic floor and ceiling: A175298, A206913, A206914, A261423, A262038, and the large block of consecutive sequences beginning at A265509.

%Y Cf. A265525.

%K nonn,base

%O 0,3

%A _N. J. A. Sloane_, Dec 10 2015