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A232268
Numbers n such that reversal (n^3) plus 1 is prime.
1
1, 3, 4, 6, 10, 19, 28, 30, 31, 40, 60, 63, 64, 66, 87, 88, 93, 96, 100, 129, 132, 135, 138, 141, 144, 184, 190, 274, 279, 280, 283, 285, 292, 294, 297, 300, 303, 310, 393, 399, 400, 402, 433, 436, 439, 589, 597, 598, 600, 612, 616, 621, 628, 630, 639, 640, 642
OFFSET
1,2
COMMENTS
If n is a multiple of 10, after reversal leading zeros are discarded before adding 1.
LINKS
EXAMPLE
a(3)= 4: 4^3= 64: reversing the digits gives 46: 46+1= 47 which is prime.
a(4)= 6: 6^3= 216: reversing the digits gives 612: 612+1= 613 which is prime.
a(12)= 63: 63^3= 250047: reversing the digits gives 740052: 740052+1= 740053 which is prime.
MAPLE
with(StringTools): KD:= proc() local a; a:= parse(Reverse(convert((n^3), string)))+1; if isprime(a) then RETURN (n): fi; end: seq(KD(), n=1..5000);
MATHEMATICA
Select[Range[500], PrimeQ[ToExpression[StringReverse[ToString[#^3]]] + 1] &]
CROSSREFS
Cf. A059008 (numbers n: n^3 reversed is prime).
Cf. A231756 (numbers n: reversal (n^2) plus 1 is prime).
Sequence in context: A018908 A353138 A052548 * A103049 A103016 A061032
KEYWORD
nonn,base,less
AUTHOR
K. D. Bajpai, Nov 22 2013
STATUS
approved