A226100 Main diagonal A(n,n) of matrix A(k,n) = n-th k-th power that becomes prime when its most significant (i.e., leftmost) decimal digit is removed.

12, 289, 729, 20151121, 371293, 2839760855281, 24160660561265139, 241100240228887100161, 3421941488772218992567, 845219547726738091164049, 7506514445791062595879589895041, 293936151563356954592299567713259041, 6657844787831219696900816415217242830357

Offset

1,1

Comments

Row 1 = A(1,n) = A226099. Row 2 = A(2,n) = A225873. Row 3 = A(3,n) = A226090. Row 4 = A(4,n) = A226092. Row 5 = A(5,n) = A226098.

Links

Table of n, a(n) for n=1..13.

Example

a(1) = A(1,1) = 12 = first number whose first power (itself) becomes prime when its most significant (or leftmost) digit is removed.
a(2) = A(2,2) = 289 = second square which becomes prime when its most significant (or leftmost) digit is removed.
a(3) =

Crossrefs

Cf. A000040, A226099, A225873, A226090, A226092, A226098.

Sequence in context: A145448 A321938 A001164 * A041267 A041264 A380096

Adjacent sequences: A226097 A226098 A226099 * A226101 A226102 A226103

Keyword

nonn,base,easy

Author

Jonathan Vos Post, May 26 2013

Status

approved