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A280268 Numbers n such that Pell(n) and Pell(n+1) have the same prime signature where Pell(n) = A000129(n). 0
2, 14, 26, 38, 86, 94, 106, 214, 218 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Initial terms are 2, 2*7, 2*13, 2*19, 2*43, 2*47, 2*53, 2*107, 2*109.
LINKS
EXAMPLE
14 is a term because A000129(14) = 2 * 13^2 * 239 and A000129(15) = 5^2 * 29 * 269.
PROG
(PARI) Pell(n) = ([2, 1; 1, 0]^n)[2, 1];
is(n) = vecsort(factor(Pell(n))[, 2]) == vecsort(factor(Pell(n+1))[, 2]);
CROSSREFS
Sequence in context: A051222 A194411 A017545 * A109080 A295083 A180877
KEYWORD
nonn,more
AUTHOR
Altug Alkan, Dec 31 2016
STATUS
approved

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Last modified March 29 11:45 EDT 2024. Contains 371278 sequences. (Running on oeis4.)