A277442 Least number k such that k^2 can be obtained from k by inserting internal (but not necessarily contiguous) digits in n different ways.

0, 10, 101, 100, 10006, 950005, 1001, 9569005, 100105, 100500, 1000, 95370001, 1000201, 102100005, 9957800, 100006, 9500005, 1100005, 100100, 1010005, 10001, 10000096, 10005005, 1000105, 1001005, 999578000, 1002600005, 12500100, 100010505, 1050500005, 1000500

Offset

0,2

Comments

a(6) = 1001.

Links

Lars Blomberg, Table of n, a(n) for n = 0..157

Example

a(2) = 101 as 101 is the least number that can be modified in two different ways in order to become its square; i.e., 101^2 equals 10201, which can be represented as 1(02)01 or 10(20)1.
a(5) = 950005 because 950005^2 = 902509500025 can be represented in 5 ways: 9(02)5(095)000(2)5, 9(02)50(95)0(0)0(2)5, 9(02)50(95)00(02)5, 9(02)50(950)00(2)5, 9(02509)5000(2)5.

Crossrefs

Cf. A046851, A277441.

Sequence in context: A304238 A231889 A066327 * A351996 A077712 A219763

Adjacent sequences: A277439 A277440 A277441 * A277443 A277444 A277445

Keyword

base,nonn

Author

Ivan N. Ianakiev, Oct 15 2016

Extensions

Terms a(5), a(7) and beyond from Lars Blomberg, Nov 20 2016

Status

approved