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A083145
Smallest nontrivial palindromic multiple of the n-th palindrome (a(n) is not equal to the n-th palindrome).
4
2, 4, 6, 8, 55, 66, 77, 88, 99, 22, 44, 66, 88, 5005, 858, 616, 616, 1881, 202, 222, 242, 262, 282, 1661, 1771, 1881, 1991, 19291, 404, 424, 444, 464, 484, 2772, 2882, 2992, 27072, 29492, 606, 626, 646, 666, 686, 3883, 3993, 37673, 38683, 14541, 808, 828
OFFSET
1,1
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)
MATHEMATICA
spm[n_]:=Module[{k=2}, While[!PalindromeQ[n k], k++]; n k]; spm/@Select[ Range[ 500], PalindromeQ] (* Harvey P. Dale, Aug 01 2021 *)
PROG
(Python)
from itertools import count
def A083145(n):
p = (c:=n+1-x)*x+int(str(c)[-2::-1] or 0) if n+1<(x:=10**(len(str(n+1>>1))-1))+(y:=10*x) else (c:=n+1-y)*y+int(str(c)[::-1] or 0)
for i in count(n+2):
if not (q:=(c:=i-x)*x+int(str(c)[-2::-1] or 0) if i<(x:=10**(len(str(i>>1))-1))+(y:=10*x) else (c:=i-y)*y+int(str(c)[::-1] or 0))%p:
return q # Chai Wah Wu, Jul 11 2024
CROSSREFS
Cf. A083146.
Sequence in context: A163502 A110995 A075401 * A085920 A228327 A081507
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Apr 25 2003
EXTENSIONS
More terms from Franklin T. Adams-Watters, May 16 2006
Definition clarified by Harvey P. Dale, Aug 01 2021
STATUS
approved