A088489 For each pair of twin primes (p,p+2) take the absolute value of the difference between p and p with digits reversed.

0, 0, 0, 54, 63, 27, 36, 54, 0, 594, 594, 792, 792, 0, 594, 495, 693, 693, 99, 198, 396, 495, 297, 297, 396, 396, 396, 99, 495, 297, 99, 693, 99, 99, 693, 8082, 270, 8352, 540, 810, 360, 7992, 6444, 8532, 270, 7812, 5814, 90, 360, 6354, 5454, 7542, 5994

Offset

1,4

Comments

9 divides each term.

Links

Table of n, a(n) for n=1..53.

Example

(17, 19) is a pair of twin primes. The absolute value of 17 - 71 is in the sequence.

Mathematica

a={}; For[n=1, n<268, n++, If[Prime[n+1]-Prime[n]==2, AppendTo[a, Abs[Prime[n] -FromDigits[Reverse[IntegerDigits[Prime[n]]]]]]]]; a

Prog

(PARI) revdiff(n) = { forprime(x=1, n, if(isprime(x+2), a=vector(x); x1=x; z=0; ln=length(Str(x1)); for(y=1, ln, a[y] = x1%10; x1=floor(x1/10); ); for(y=1, ln, z += a[y]*10^(ln-y); ); print1(abs(z-x)" "); ) ) }

Crossrefs

Sequence in context: A095501 A318235 A158989 * A025331 A025323 A157934

Adjacent sequences: A088486 A088487 A088488 * A088490 A088491 A088492

Keyword

base,nonn,less

Author

Cino Hilliard, Nov 09 2003

Extensions

Edited by Stefan Steinerberger, Jun 12 2007

Status

approved