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A135411
Numbers n with property that for each single digit d of n, we can also see the decimal expansion of d+2 as a substring of n.
0
113579, 113597, 113759, 113795, 113957, 113975, 115379, 115397, 115739, 115793, 115937, 115973, 117359, 117395, 117539, 117593, 117935, 117953, 119357, 119375, 119537, 119573, 119735, 119753, 311579, 311597, 311759, 311795, 311957, 311975
OFFSET
1,1
COMMENTS
There are exactly 120 six-digit such integers.
These include 24 primes: 113759, 113957, 115793, 117539, 311957, 351179, 375119, 511793, 531197, 539711, 573119, 579113, 579311, 591137, 593711, 711539, 739511, 751139, 751193, 759113, 793511, 911357, 937511, 971153;
and 36 semiprimes: 113579, 115397, 115937, 117953, 119537, 119573, 119753, 311579, 311759, 359117, 375911, 379511, 391157, 395711, 397115, 511379, 511397, 511739, 539117, 571139, 593117, 711593, 731195, 753119, 753911, 791135, 911573, 931157, 935117, 935711, 937115, 951137, 957113, 957311, 975113, 975311.
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Feb 17 2008
STATUS
approved