A391022 Minimal square obtained by concatenating n distinct nonzero squares in ascending order.

1, 49, 1936, 1416100, 143664196, 1491615214489, 149225256576841, 1416368119690022500

Offset

1,2

Links

Table of n, a(n) for n=1..8.

Formula

a(n) >= A019521(n). - Michael S. Branicky, Nov 25 2025

Example

For n = 2, the minimal value is a(2) = 49. Indeed, concatenating 2^2 = 4 and 3^2 = 9 produces 49, which is itself a perfect square 7^2. There is no smaller integer that is both a square and the concatenation of two distinct nonzero squares.

Crossrefs

Cf. A000290, A006716, A087354, A019521.

Sequence in context: A367378 A065785 A163927 * A245036 A061615 A049682

Adjacent sequences: A391019 A391020 A391021 * A391023 A391024 A391025

Keyword

nonn,base,more

Author

Jean-Marc Rebert, Nov 25 2025

Extensions

a(4) and a(6) corrected by and a(8) from Michael S. Branicky, Nov 25 2025

Status

approved