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A244542 Palindromes n such that n +/- the product of digits of n are both palindromes. 0
1, 2, 3, 4, 101, 202, 252, 303, 404, 505, 606, 707, 808, 909, 1001, 2002, 3003, 4004, 5005, 6006, 7007, 8008, 9009, 10001, 10101, 10201, 10301, 10401, 10501, 10601, 10701, 10801, 10901, 11011, 12021, 13031, 14041, 15051, 15451, 16061, 17071, 18081, 19091, 20002, 20102, 20202 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

These are the palindromes in A244541.

All palindromes with a zero will be in this sequence.

The palindromes that do not contain a zero but do satisfy the definition begin 1, 2, 3, 4, 252, 15451, 25152, 25252, 25352, 25452, 36563, 51415, 52125, 52225, 52325, 52425, 63536, 92529, 1455541, 1545451, 1954591 . . . - Harvey P. Dale, May 14 2019

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

101 - 1*0*1 and 101 + 1*0*1 are both palindromes (still 101). So 101 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, 10^5, if(rev(n)==n, dig=digits(n); p=prod(k=1, #dig, dig[k]); mi=n-p; ma=n+p; if(rev(mi)==mi&&rev(ma)==ma, print1(n, ", "))))

CROSSREFS

Cf. A007954, A244541.

Sequence in context: A262526 A171564 A244541 * A085935 A100981 A001095

Adjacent sequences:  A244539 A244540 A244541 * A244543 A244544 A244545

KEYWORD

nonn,base

AUTHOR

Derek Orr, Jun 29 2014

STATUS

approved

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Last modified May 18 19:58 EDT 2021. Contains 344002 sequences. (Running on oeis4.)