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A027725 Palindromes of form k^2 + k + 8. 3
8, 878, 41014, 81518, 8558558, 8617168, 415242514, 874414478, 88279997288, 8035521255308, 8053537353508, 8942435342498, 8984014104898, 82375268486257328, 8563985811185893658, 41023644811311844632014, 87279499176567199497278, 462070049490878094940070264, 467190356216898612653091764 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Palindromes h such that 4*h - 31 is a square. - Bruno Berselli, Aug 29 2018

LINKS

Table of n, a(n) for n=1..19.

P. De Geest, Palindromic Quasi_Over_Squares of the form n^2+(n+X)

MATHEMATICA

palQ[n_] := Block[{d = IntegerDigits[n]}, d == Reverse[d]]; f[n_] := n^2 + n + 8; Select[f@ Range[0, 3*10^5], palQ] (* Giovanni Resta, Aug 29 2018 *)

CROSSREFS

Cf. A027724, A027693, A027723, A027727.

Sequence in context: A097818 A262379 A175411 * A265239 A290023 A112578

Adjacent sequences:  A027722 A027723 A027724 * A027726 A027727 A027728

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

EXTENSIONS

a(14)-a(19) from Giovanni Resta, Aug 29 2018

STATUS

approved

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Last modified June 30 09:38 EDT 2022. Contains 354920 sequences. (Running on oeis4.)