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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
OFFSET
1,1
COMMENTS
Palindromes h such that 4*h - 31 is a square. - Bruno Berselli, Aug 29 2018
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
KEYWORD
nonn,base
EXTENSIONS
a(14)-a(19) from Giovanni Resta, Aug 29 2018
STATUS
approved