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A257554
Numbers k such that A007954(k) divides k and k divides A007954(k)^2.
3
1, 2, 3, 4, 5, 6, 7, 8, 9, 36, 128, 175, 384, 735, 1296, 2916, 18432, 34992, 82944, 139968, 442368, 2333772, 4128768, 9289728, 12192768, 13226976, 13395375, 13436928, 27869184, 49787136, 376233984, 429981696, 1269789696, 2633637888, 4161798144, 16728477696, 19999187712, 41479796736, 72236924928
OFFSET
1,2
COMMENTS
There are 66 terms below 10^400 with the largest containing 46 digits.
LINKS
PROG
(PARI) for(n=1, 10^6, d=digits(n); p=prod(i=1, #d, d[i]); if(p && n%p==0 && p^2%n==0, print1(n, ", ") )) \\ Derek Orr, Apr 29 2015
CROSSREFS
Intersection of A007602 and A128606.
Sequence in context: A316147 A080161 A345405 * A270393 A257787 A098771
KEYWORD
nonn,base
AUTHOR
Max Alekseyev, Apr 29 2015
STATUS
approved