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A244548
Palindromes n with nonzero digits such that n +/- the product of digits of n are both palindromes.
0
1, 2, 3, 4, 252, 15451, 25152, 25252, 25352, 25452, 36563, 51415, 52125, 52225, 52325, 52425, 63536, 92529, 1455541, 1545451, 1954591, 2255522, 2525252, 2853582, 2856582, 3354533, 3534353, 4155514, 4453544, 4456544, 4515154, 4543454, 4546454, 5145415, 5225225, 5334335, 5415145
OFFSET
1,2
COMMENTS
These are the palindromes in A244547.
EXAMPLE
252 has all digits > 0. 252 is a palindrome, 252 - 2*5*2 = 232 is a palindrome, and 252 + 2*5*2 = 272 is a palindrome. Thus 252 is a member of this sequence.
PROG
(PARI) rev(n)={r=""; for(i=1, #digits(n), r=concat(Str(digits(n)[i]), r)); return(eval(r))}
for(n=1, 10^7, if(rev(n)==n, dig=digits(n); p=prod(k=1, #dig, dig[k]); if(p!=0, mi=n-p; ma=n+p; if(rev(mi)==mi&&rev(ma)==ma, print1(n, ", ")))))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Derek Orr, Jun 29 2014
STATUS
approved