A219250 Lexicographically earliest sequence of nonnegative integers such that the absolute difference of any two adjacent digits is prime.

0, 2, 4, 1, 3, 5, 7, 9, 6, 8, 13, 14, 16, 18, 30, 20, 24, 25, 27, 29, 41, 31, 35, 36, 38, 50, 52, 42, 46, 47, 49, 61, 63, 53, 57, 58, 64, 68, 69, 70, 72, 74, 75, 79, 202, 92, 94, 96, 81, 83, 85, 86, 97, 203, 130, 205, 207, 241, 302, 413, 131, 303, 135, 242, 414, 136, 138, 141, 305, 246, 142, 416, 146, 147, 247, 249

Offset

1,2

Comments

See A219249 for the version allowing only positive integers, i.e., starting with a(1)=1.

See A219248 (= range of A219250) for the numbers which occur in this sequence, and A219251 for the complement.

A182177 is the analog of this sequence for replacing "absolute difference" by "sum", A182178 is the same analog for A219249; A182175 is the analog of A219248 and A219110 corresponds to A219251.

Links

Table of n, a(n) for n=1..76.

M. F. Hasler in reply to E. Angelini, Re: Any digit-pair in S sums to a prime, SeqFan list, Apr 11 2013

Prog

(PARI) {(n, a=[0], u=0)->while(#a<n, u+=1<<a[#a]; for(t=a[1]+1, 9e9, bittest(u, t)&next; my(d=concat(a[#a]%10, digits(t))); for(i=2, #d, isprime(abs(d[i-1]-d[i]))||next(2)); a=concat(a, t); break)); a}

Crossrefs

Sequence in context: A173658 A277618 A358054 * A361643 A282891 A117137

Adjacent sequences: A219247 A219248 A219249 * A219251 A219252 A219253

Keyword

nonn,base

Author

M. F. Hasler, Apr 11 2013

Status

approved