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A028504 Palindromes of form n(n+2); or palindromes 1 less than a square. 1
0, 3, 8, 99, 323, 575, 4224, 5775, 9999, 36863, 42024, 999999, 3055503, 3640463, 5597955, 8803088, 32855823, 99999999, 360696063, 422919224, 9999999999, 30485858403, 30536863503, 32154945123, 59080108095, 86310801368 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

P. De Geest, Palindromic quasipronic numbers of the form n(n+2)

EXAMPLE

4224 belongs to this sequence as 4225 = 65^2.

PROG

(ARIBAS): stop := 400000; m := 1; while m < stop do s := m*m - 1; if s = int_reverse(s) then write(s, " "); end; inc(m); end;

CROSSREFS

Cf. A005563, A028503.

Sequence in context: A114737 A099296 A066619 * A123279 A134803 A030063

Adjacent sequences:  A028501 A028502 A028503 * A028505 A028506 A028507

KEYWORD

nonn,base

AUTHOR

Patrick De Geest (pdg(AT)worldofnumbers.com)

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Last modified February 12 03:59 EST 2012. Contains 205360 sequences.