|
| |
|
|
A162705
|
|
Numbers that are the sum of two reversed consecutive primes in more than one way.
|
|
1
|
|
|
|
582, 1026, 1032, 1038, 1092, 1122, 1128, 1134, 1152, 1296, 1644, 1716, 4152, 4344, 4602, 4932, 5068, 5562, 5808, 8706, 8862, 8988, 9012, 9036, 9066, 9264, 9726, 10110, 10308, 10326, 10342, 10398, 10638, 10698, 10764, 10794, 10806, 10866, 10912, 10944, 10998
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
Subsequence of A162704. - R. J. Mathar, Jul 13 2009
|
|
|
LINKS
|
Sean A. Irvine, Table of n, a(n) for n = 1..115
|
|
|
EXAMPLE
|
582 = R(191) + R(193) = 191 + 391 and R(683) + R(691) = 386 + 196.
1032 = R(113) + R(127) = 311 + 721 = R(613) + R(617) = 316 + 716.
|
|
|
MAPLE
|
read("transforms") ; A055642 := proc(n) max(1, ilog10(n)+1) ; end:
A004087 := proc(n) option remember; digrev(ithprime(n)) ; end:
isA162705 := proc(n) c := 0 ; for i from 1 do p := ithprime(i) ; if A055642(p) > A055642(n) then break; fi; if A004087(i)+A004087(i+1) = n then c := c+1; fi; od: RETURN(c > 1); end:
for n from 1 to 10000 do if isA162705(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Jul 13 2009
|
|
|
MATHEMATICA
|
Sort[Transpose[Select[Tally[FromDigits[Reverse[IntegerDigits[#[[1]]]]] + FromDigits[Reverse[IntegerDigits[#[[2]]]]]&/@Partition[Prime[Range[ 2000]], 2, 1]], Last[#]>1&]][[1]]] (* Harvey P. Dale, Nov 14 2012 *)
|
|
|
CROSSREFS
|
Cf. A004087, A162704.
Sequence in context: A172835 A172883 A260541 * A244344 A059468 A350663
Adjacent sequences: A162702 A162703 A162704 * A162706 A162707 A162708
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Claudio Meller, Jul 11 2009
|
|
|
EXTENSIONS
|
Keyword:base plus more terms from R. J. Mathar, Jul 13 2009
Typo in first example corrected by R. J. Mathar, Jul 22 2009
More terms from Sean A. Irvine, Nov 14 2010
|
|
|
STATUS
|
approved
|
| |
|
|
