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A081982
Primes p such that p+1 is divisible by the digital product (of nonzero digits) of p.
6
11, 23, 101, 113, 131, 167, 211, 233, 311, 431, 863, 1013, 1021, 1031, 1061, 1103, 1201, 1217, 1223, 1259, 1301, 1601, 1619, 1637, 1721, 1823, 2003, 2011, 2111, 2687, 3011, 3023, 3203, 4111, 4703, 6011, 6047, 6101, 6173, 6263, 6911, 7013
OFFSET
1,1
COMMENTS
Contains A020449 and A107612 (except 2). - Robert Israel, Nov 09 2017
LINKS
EXAMPLE
167 is a term as 168 is divisible by 1*6*7 = 42.
MAPLE
filter:= proc(n)
isprime(n) and
n+1 mod convert(subs(0=NULL, convert(n, base, 10)), `*`) = 0
end proc:
select(filter, [seq(i, i=3..10000, 2)]); # Robert Israel, Nov 09 2017
PROG
(PARI) isok(p) = isprime(p) && (d=digits(p)) && !((p+1) % prod(k=1, #d, if (d[k], d[k], 1))); \\ Michel Marcus, Nov 09 2017
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Apr 04 2003
EXTENSIONS
More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003
STATUS
approved