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A027571
Numbers k such that k^2 + (k+1)^2 is palindromic.
3
0, 1, 9, 12, 16, 919, 1257, 1262, 1621, 1706, 170706, 904280, 1258182, 7901014, 8659929, 12458597, 17070706, 80472264, 1616689803, 1680689788, 1705387643, 7360311900, 8032814139, 8055329360, 12574461617, 16794058711, 165058650666, 844706005220, 1250999800012, 1255589965852
OFFSET
1,3
COMMENTS
a(50) > 70710678118654752440. - Patrick De Geest, May 25 2021
LINKS
Patrick De Geest, Table of n, a(n) for n = 1..49 (terms a(1)..a(29) from Giovanni Resta)
PROG
(PARI) isok(m) = my(d=digits(m^2+(m+1)^2)); d == Vecrev(d); \\ Michel Marcus, Jan 05 2019
CROSSREFS
A050236 is a subsequence.
Sequence in context: A373267 A076674 A176062 * A342757 A154631 A199593
KEYWORD
nonn,base
EXTENSIONS
a(18)-a(21) from Donovan Johnson, Aug 26 2012
a(22)-a(29) from Giovanni Resta, Aug 06 2019
a(1)=0 added by Patrick De Geest, May 25 2021
STATUS
approved