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.

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

Links

Table of n, a(n) for n=1..51.

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

Adjacent sequences: A069552 A069553 A069554 * A069556 A069557 A069558

Keyword

nonn,base

Author

Amarnath Murthy, Mar 22 2002

Extensions

More terms from Francois Jooste (phukraut(AT)hotmail.com), Mar 06 2003

Status

approved