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A103992 Palindromic primes: insert a digit between digits of the previous term. 0
11, 101, 16061, 126202621, 13236323032363231 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Inserted digits are 0, 6, 2, 3. If we search only for minimal inserted digit and start with 11, the sequence ends at 5th term. - Ray Chandler, Feb 25 2005

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

Start with 11; insert 0 between digits, 101 is prime; insert 6 between digits, 16061 is prime, etc.

MATHEMATICA

nxt[n_]:=SelectFirst[FromDigits/@Table[Riffle[IntegerDigits[n], i], {i, 0, 9}], PrimeQ]; NestList[nxt, 11, 4] (* The program uses the SelectFirst function from Mathematica version 10 *) (* Harvey P. Dale, Aug 08 2015 *)

CROSSREFS

Sequence in context: A082620 A199304 A156668 * A185949 A001387 A247863

Adjacent sequences:  A103989 A103990 A103991 * A103993 A103994 A103995

KEYWORD

fini,nonn,base

AUTHOR

Zak Seidov, Feb 23 2005

EXTENSIONS

Corrected by Ray Chandler, Feb 25 2005

STATUS

approved

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Last modified December 7 07:15 EST 2016. Contains 278841 sequences.