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A048343 Total number of distinct palindromes of form 'n-digit number' x 'n-digit number_reversed' (n-digit number not palindromic). 3
0, 1, 3, 10, 19, 44, 86, 171, 308, 551, 920 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
EXAMPLE
E.g., 3 solutions for 3-digit numbers: 102 * 201 = 20502; 112 * 211 = 23632; 122 * 221 = 26962.
PROG
(Python)
def A048343(n):
....y, plist = 0, []
....for i in range(10**(n-1), 10**n):
........s1 = str(i)
........s2 = s1[::-1]
........if s1 != s2:
............p = i*int(s2)
............if not p in plist:
................sp = str(p)
................if sp == sp[::-1]:
....................plist.append(p)
....................y += 1
....return y # Chai Wah Wu, Sep 05 2014
CROSSREFS
Cf. A048344.
Sequence in context: A160002 A294421 A027177 * A056789 A174476 A098645
KEYWORD
nonn,base,more
AUTHOR
Patrick De Geest, Feb 15 1999
EXTENSIONS
More terms from Sam Handler (sam_5_5_5_0(AT)yahoo.com), Aug 18 2006
Offset changed and two terms added by Lars Blomberg, Nov 25 2011
STATUS
approved

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Last modified July 24 22:37 EDT 2024. Contains 374585 sequences. (Running on oeis4.)