A270895 Sierpiński numbers that are squares.

18213931681, 5044241991721, 6093734165401, 6278567569849, 17919144076201, 52536446729209, 56470430531761, 72659547739249, 107737943736721, 123343213788001, 136925780937841, 170306127919321, 211292941174561, 296693149397089, 321058916825689

Offset

1,1

Comments

This sequence contains infinitely many numbers that end in 5. See also A233469.

Links

Table of n, a(n) for n=1..15.

Wikipedia, Sierpinski number

Formula

A000290 INTERSECT A076336.

a(n) = A270896(n)^2.

Crossrefs

Cf. A076336, A233469, A270896.

Sequence in context: A202724 A115537 A233486 * A273186 A185932 A262533

Adjacent sequences: A270892 A270893 A270894 * A270896 A270897 A270898

Keyword

nonn,hard

Author

Arkadiusz Wesolowski, Mar 25 2016

Status

approved