A171986 Concatenate distance to previous prime & distance to next prime. If no previous prime, use 0.

1, 1, 12, 11, 22, 11, 24, 13, 22, 31, 42, 11, 24, 13, 22, 31, 42, 11, 24, 13, 22, 31, 46, 15, 24, 33, 42, 51, 62, 11, 26, 15, 24, 33, 42, 51, 64, 13, 22, 31, 42, 11, 24, 13, 22, 31, 46, 15, 24, 33, 42, 51, 66, 15, 24, 33, 42, 51, 62, 11, 26, 15, 24, 33, 42, 51, 64, 13, 22, 31

Offset

1,3

Links

Table of n, a(n) for n=1..70.

Example

a(7)=24 as 5 is largest previous prime to 7, distance is 2, & 11 is smallest next prime to 7, distance 4. Concatenate 2 & 4 gives 24.

Crossrefs

Sequence in context: A019330 A086045 A072220 * A254717 A195748 A038337

Adjacent sequences: A171983 A171984 A171985 * A171987 A171988 A171989

Keyword

nonn,base

Author

Gerald Hillier, Jan 21 2010

Status

approved