login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A099744 Palindromes n such that 10n01 is a prime. 2
3, 5, 6, 222, 282, 353, 434, 555, 626, 656, 747, 828, 858, 929, 939, 10301, 10601, 11411, 11711, 12821, 12921, 13431, 13731, 14141, 14241, 14741, 15951, 16161, 17171, 17771, 18381, 18981, 19191, 19491, 19991, 20402, 20702, 22022, 22322 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MAPLE

read transforms; pal:=[]; for n from 0 to 8000 do if digrev(n) = n then pal:=[op(pal), n]; fi; od:

t0:=[]; u0:=[]; for n from 1 to nops(pal) do m:=pal[n]; p0:="10"; p1:="01"; t1:=cat(p0, m, p1); t1:=convert(t1, decimal, 10); if isprime(t1) then t0:=[op(t0), m]; u0:=[op(u0), t1]; fi; od: t0; # u0 gives A099746.

MATHEMATICA

p = Select[ Range[ 22322], # == FromDigits[ Reverse[ IntegerDigits[ # ]]] &]; Select[p, PrimeQ[ FromDigits[ Join[{1, 0}, IntegerDigits[ # ], {0, 1}]]] &] (from Robert G. Wilson v Nov 20 2004)

CROSSREFS

Cf. A002113, A099746, A032672, A099720, A100026, A100027.

Sequence in context: A137082 A099414 A004785 * A024601 A173013 A085090

Adjacent sequences:  A099741 A099742 A099743 * A099745 A099746 A099747

KEYWORD

nonn,easy,base

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Nov 19 2004

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 19 2004

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 14:50 EST 2012. Contains 206050 sequences.