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Terms in A006512 containing the digit "6" at least once, such that changing every "6" to a "9" and vice versa yields a larger term in A006512.
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%I #18 Nov 19 2024 03:16:10

%S 1063,3361,7561,10861,14563,16141,16693,26881,32611,36343,55633,61153,

%T 62971,62983,64153,68713,70621,76963,100363,106453,115603,116101,

%U 131641,136993,146521,152641,155863,160711,161341,161971,166741,167341,167863

%N Terms in A006512 containing the digit "6" at least once, such that changing every "6" to a "9" and vice versa yields a larger term in A006512.

%C 1063 is in A006512 and so is 1093, obviously 1093 > 1063, therefore 1063 is in the sequence.

%C If the definition of the permitted terms included any term in A006512, instead of a larger term, the sequence would also contain 19963, 79693, 92671, 92683, and 139663. - _James C. McMahon_, Nov 17 2024

%t gtp=Select[Prime[Range[PrimePi[400000]]],PrimeQ[#-2]&];Select[gtp,MemberQ[IntegerDigits[#],6]&&MemberQ[gtp,r=FromDigits[IntegerDigits[#]/.{6->9,9->6}]]&&r>#&] (* _James C. McMahon_, Nov 17 2024 *)

%Y Cf. A006512.

%K base,nonn,less

%O 1,1

%A _Pierre CAMI_, Oct 05 2006

%E Edited, corrected and extended by _Pierre CAMI_ and _Stefan Steinerberger_, Aug 14 2007