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A262087
Largest palindrome p such that n-p is again a palindrome, or 0 if no such p exists.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 9, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 0, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 0, 33, 33, 33, 33, 33, 33, 33, 33, 33, 33, 0, 44, 44, 44, 44, 44, 44, 44, 44, 44, 44, 0, 55, 55, 55, 55, 55, 55, 55, 55, 55, 55, 0, 66, 66, 66, 66, 66, 66, 66, 66, 66, 66, 0, 77, 77, 77, 77, 77, 77
OFFSET
0,3
FORMULA
a(n) = 0 for n in {0} union A035137.
PROG
(PARI) a(N, P=A261423(N))=until(N<2*P=A261423(P-1), is_A002113(N-P)&&return(P))
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Sep 10 2015
STATUS
approved