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A048398 Primes with consecutive digits that differ exactly by 1. 22
2, 3, 5, 7, 23, 43, 67, 89, 101, 787, 4567, 12101, 12323, 12343, 32321, 32323, 34543, 54323, 56543, 56767, 76543, 78787, 78989, 210101, 212123, 234323, 234343, 432121, 432323, 432343, 434323, 454543, 456767, 654323, 654343, 678767, 678989 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Or, primes in A033075. - Zak Seidov, Feb 01 2011
REFERENCES
J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 67, p. 23, Ellipses, Paris 2008.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000 (terms n = 1..1500 from Zak Seidov)
MATHEMATICA
Select[Prime[Range[10000]], # < 10 || Union[Abs[Differences[IntegerDigits[#]]]] == {1} &]
PROG
(Haskell)
a048398 n = a048398_list !! (n-1)
a048398_list = filter ((== 1) . a010051') a033075_list
-- Reinhard Zumkeller, Feb 21 2012, Nov 04 2010
(Python 3.2 or higher)
from itertools import product, accumulate
from sympy import isprime
A048398_list = [2, 3, 5, 7]
for l in range(1, 17):
for d in [1, 3, 7, 9]:
dlist = [d]*l
for elist in product([-1, 1], repeat=l):
flist = [str(d+e) for d, e in zip(dlist, accumulate(elist)) if 0 <= d+e < 10]
if len(flist) == l and flist[-1] != '0':
n = 10*int(''.join(flist[::-1]))+d
if isprime(n):
A048398_list.append(n)
A048398_list = sorted(A048398_list) # Chai Wah Wu, May 31 2017
CROSSREFS
Cf. A010051; intersection of A033075 and A000040.
Sequence in context: A362678 A106711 A235110 * A059170 A068710 A120805
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Apr 15 1999
STATUS
approved

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Last modified April 19 16:52 EDT 2024. Contains 371794 sequences. (Running on oeis4.)