A247069 a(n) = number of distinct primes obtained when inserting 1 anywhere in A069246(n).

2, 2, 2, 2, 3, 3, 2, 2, 3, 4, 3, 3, 3, 2, 2, 3, 4, 4, 2, 3, 4, 3, 3, 4, 3, 5, 5, 5, 5, 4, 4, 4, 6, 4, 5, 5, 5, 6, 5, 4, 6, 6, 5, 4, 5, 6, 7, 6, 5, 5, 4, 5, 5, 6, 3, 5, 6, 5, 6, 5, 6, 3, 6, 7, 5, 5, 4, 5, 5, 5, 6, 4, 7, 4, 4, 6, 6, 4, 5, 7, 3, 3, 3, 4, 3, 5, 2, 3, 5, 5, 6, 7, 6, 4, 7, 5, 6, 5, 7, 3, 8

Offset

1,1

Comments

Among the first 145 terms the largest is a(140)=9 because inserting 1 in 12 places into A069246(140)=18064911343, we get only 9 distinct primes (in the order of their appearances): 118064911343, 181064911343, 180164911343, 180614911343, 180641911343, 180649111343, 180649113143, 180649113413, 180649113431.

Links

Zak Seidov, Table of n, a(n) for n = 1..145

Example

a(7)=2 because inserting 1 in 4 possible places into A069246(7)=151 we get only 2 distinct primes, 1151 and 1511.

Crossrefs

Cf. A069246.

Sequence in context: A196046 A152724 A081743 * A367008 A366800 A366799

Adjacent sequences: A247066 A247067 A247068 * A247070 A247071 A247072

Keyword

nonn,base

Author

Zak Seidov, Nov 17 2014

Status

approved