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A069555
a(n) = smallest non-palindromic number k such that k and its digit reversal are divisible by n, or 0 if n is a multiple of 10.
0
10, 20, 12, 40, 50, 24, 70, 80, 18, 0, 110, 48, 1495, 2072, 510, 2192, 1156, 216, 1710, 0, 168, 220, 1610, 840, 5200, 2496, 1998, 2520, 2320, 0, 1178, 2304, 132, 2720, 5075, 216, 1110, 2166, 1677, 0, 1066, 2436, 9890, 440, 540, 4140, 1410, 2304, 3430, 0, 1479
OFFSET
1,1
EXAMPLE
a(12) = 48 as 12 divides 48 as well as 84.
MAPLE
np := proc(N::posint, i::posint) local d, e; description "if 'N' is not palindromic and 'i' divides both 'N' and its reverse then returns 'true', else 'false'"; d := convert(N, base, 10); e := sum(d[j]*10^(nops(d)-j), j=1..nops(d)); if N=e then return false else if N mod i=0 and e mod i=0 then return true else return false fi; fi; end proc; nps := proc(J::posint, K::posint) local f, F, FU, i; description "returns the sequence of smallest numbers that satisfy 'np' (or number is 0 if the sequence position is divisible by 10) starting at sequence position 'J' and checking numbers up to 'K'; to get a sequence from 1 to the maximum position allowable by 'K', set 'J=1'."; f := (i, M)->`if`(i mod 10=0, 0, min(seq(`if`(np(N, i)=true, N, NULL), N=i..M))); i := J; while f(i, K)<>infinity do F(i) := `if`(i mod 10=0, 0, f(i, K)); i := i+1 od; FU := [seq(F(ii), ii=J..i-1)]; return FU, `if`(FU=[], printf("no numbers found; try raising 'K'."), printf("the sequence from positions %d to %d.", J, i-1)); end proc;
CROSSREFS
Cf. A069554.
Sequence in context: A294069 A249585 A067524 * A069035 A245065 A040090
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Mar 22 2002
EXTENSIONS
More terms from Francois Jooste (phukraut(AT)hotmail.com), Mar 06 2003
STATUS
approved