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A255872
Smallest Rhonda number to base b = n-th composite number, A002808(n).
14
10206, 855, 1836, 15540, 1568, 560, 11475, 2392, 1000, 1470, 1815, 1632, 2695, 2080, 6764, 7788, 4797, 3094, 3024, 1944, 756, 5661, 8232, 1000, 12296, 5824, 4624, 4851, 8262, 6561, 16583, 14616, 6545, 7225, 11310, 18382, 1995, 16896, 2940, 23465, 8464, 3348
OFFSET
1,1
COMMENTS
See A099542 for definition of Rhonda numbers and for more links.
LINKS
Eric Weisstein's World of Mathematics, Rhonda Number
EXAMPLE
. n | b | a(n) | a(n) in base b | factorization
. ----+----+--------------------+-----------------+--------------
. 1 | 4 | 10206 = A100968(1) | [2,1,3,3,1,3,2] | 2*3^6*7
. 2 | 6 | 855 = A100969(1) | [3,5,4,3] | 3^2*5*19
. 3 | 8 | 1836 = A100970(1) | [3,4,5,4] | 2^2*3^3*17
. 4 | 9 | 15540 = A100973(1) | [2,3,2,7,6] | 2^2*3*5*7*37
. 5 | 10 | 1568 = A099542(1) | [1,5,6,8] | 2^5*7^2
. 6 | 12 | 560 = A100971(1) | [3,10,8] | 2^4*5*7
. 7 | 14 | 11475 = A100972(1) | [4,2,7,9] | 3^3*5^2*17
. 8 | 15 | 2392 = A100974(1) | [10,9,7] | 2^3*13*23
. 9 | 16 | 1000 = A100975(1) | [3,14,8] | 2^3*5^3
. 10 | 18 | 1470 = A255735(1) | [4,9,12] | 2*3*5*7^2
. 11 | 20 | 1815 = A255732(1) | [4,10,15] | 3*5*11^2
. 12 | 21 | 1632 | [3,14,15] | 2^5*3*17
. 13 | 22 | 2695 | [5,12,11] | 5*7^2*11
. 14 | 24 | 2080 | [3,14,16] | 2^5*5*13
. 15 | 25 | 6764 | [10,20,14] | 2^2*19*89
. 16 | 26 | 7788 | [11,13,14] | 2^2*3*11*59
. 17 | 27 | 4797 | [6,15,18] | 3^2*13*41
. 18 | 28 | 3094 | [3,26,14] | 2*7*13*17
. 19 | 30 | 3024 = A255736(1) | [3,10,24] | 2^4*3^3*7
. 20 | 32 | 1944 | [1,28,24] | 2^3*3^5
PROG
(Haskell)
a255872 n = head $ filter (rhonda b) $ iterate zeroless 1 where
-- function rhonda as defined in A099542
zeroless x = 1 + if r < b - 1 then x else b * zeroless x'
where (x', r) = divMod x b
b = a002808 n
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 08 2015
STATUS
approved