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A257554 Numbers n such that A007954(n) divides n and n divides A007954(n)^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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

There are 66 terms below 10^400 with the largest containing 46 digits.

LINKS

Max Alekseyev, Table of n, a(n) for n = 1..66

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: A064154 A316147 A080161 * A270393 A257787 A098771

Adjacent sequences:  A257551 A257552 A257553 * A257555 A257556 A257557

KEYWORD

nonn,base

AUTHOR

Max Alekseyev, Apr 29 2015

STATUS

approved

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Last modified July 9 14:56 EDT 2020. Contains 335543 sequences. (Running on oeis4.)