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A260157
Smallest term of the first run of at least n consecutive integers which are not sums of 2 squares.
2
3, 6, 21, 21, 75, 91, 186, 378, 987, 987, 1494, 1494, 1494, 1494, 5166, 5166, 5166, 5166, 16110, 16869, 31658, 31658, 31658, 52394, 101350, 101350, 101350, 105573, 241883, 241883, 284003, 284003, 284003, 685542, 1437354, 1751297, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867, 1853867
OFFSET
1,1
EXAMPLE
None of 21, 22, 23, and 24 is representable as a sum of two squares. Previous record of run length was 2, hence a(3)=a(4)=21.
MATHEMATICA
t = Select[Range[10^4], SquaresR[2, #] == 0 &]; SelectFirst[t, Function[n, ContainsAll[t, n + Range@ #]]] & /@ Range[0, 15] (* Michael De Vlieger, Nov 09 2015, Version 10.2 *)
CROSSREFS
Cf. A022544.
Sequence in context: A370996 A328567 A064366 * A101719 A173165 A210504
KEYWORD
nonn
AUTHOR
Ivan Neretin, Nov 09 2015
STATUS
approved