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A027571 Numbers n such that n^2 + (n+1)^2 is palindromic. 3
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..31 (terms < 2*10^12)

P. De Geest, Palindromic Sums of Squares of Consecutive Integers

PROG

(PARI) isok(m) = my(d=digits(m^2+(m+1)^2)); d == Vecrev(d); \\ Michel Marcus, Jan 05 2019

CROSSREFS

Cf. A027572.

A050236 is a subsequence.

Sequence in context: A084375 A076674 A176062 * A154631 A199593 A174525

Adjacent sequences:  A027568 A027569 A027570 * A027572 A027573 A027574

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

EXTENSIONS

a(17)-a(20) from Donovan Johnson, Aug 26 2012

a(21)-a(28) from Giovanni Resta, Aug 06 2019

STATUS

approved

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Last modified October 19 20:55 EDT 2019. Contains 328224 sequences. (Running on oeis4.)