1,2

The sequence is started with a(1)=0 and always extended with the smallest integer not yet present in the sequence and not leading to a contradiction.

Jean-Marc Falcoz, Table of n, a(n) for n = 1..10001

Prime sum of successive terms:

0+2 is prime; 2+1 is prime; 1+4 is prime; ... 6+7 is prime; 7+412 is prime; 412+9 is prime; etc.

Prime sum of successive digits: 0+2 is prime; 2+1 is prime; 1+4 is prime; ... 6+7 is prime; 7+4 is prime; 4+1 is prime; 1+2 is prime; etc.

Cf. A217555.

Sequence in context: A294096 A128280 A182177 * A106625 A275902 A008347

Adjacent sequences: A281875 A281876 A281877 * A281879 A281880 A281881

nonn,base

Eric Angelini and Jean-Marc Falcoz, Feb 01 2017

approved