A069849 Number of distinct primes obtained by inserting an 8 at all possible places in n. This includes prefixing.

0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 2, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0

Offset

1,11

Links

Table of n, a(n) for n=1..105.

Example

See the example in A069842.

Mathematica

Table[ Count[ PrimeQ[ Union[ FromDigits /@ Table[ Insert[ IntegerDigits[n], 8, j], {j, 1, Floor[ Log[10, n] + 2]}]]], True], {n, 1, 105}]

Crossrefs

Cf. A069842, A069843, A069844, A069845, A069846, A069847, A069848, A069850 and A069851.

Sequence in context: A086008 A083910 A069843 * A138045 A072507 A004530

Adjacent sequences: A069846 A069847 A069848 * A069850 A069851 A069852

Keyword

base,nonn

Author

Amarnath Murthy, Apr 16 2002

Extensions

Edited, corrected and extended by Robert G. Wilson v, Apr 18 2002

Status

approved