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A028978 Product of prime and previous prime is palindromic. 3
3, 11, 19, 193, 1061, 1934071 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No further terms < 4.5*10^8.

LINKS

Table of n, a(n) for n=1..6.

P. De Geest, More palindromic products of integer sequences

EXAMPLE

19 belongs to this sequence as 17*19 = 323.

MATHEMATICA

p=2; t={}; Do[q=NextPrime[p]; If[Reverse[x=IntegerDigits[p*q]]==x, AppendTo[t, q]]; p=q, {n, 150000}]; t (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A028979, A028888.

Sequence in context: A075226 A192598 * A082628 A166096 A139220 A139221

Adjacent sequences:  A028975 A028976 A028977 * A028979 A028980 A028981

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified November 25 23:44 EST 2014. Contains 250017 sequences.