1,3

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

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.

Sequence in context: A019330 A086045 A072220 * A254717 A195748 A038337

Adjacent sequences: A171983 A171984 A171985 * A171987 A171988 A171989

nonn,base

Gerald Hillier, Jan 21 2010

approved