OFFSET
1,1
COMMENTS
Terms have at least one 3 or at least one 7. - David A. Corneth, May 26 2023
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10871 (terms <= 10^43)
David A. Corneth, PARI program
EXAMPLE
a(4)=337 since 337, 373 and 733 all have the same sorted list of digits [3,3,7].
MAPLE
a:=proc(b, n) local nn: nn:=convert(n, base, b): if isprime(n) and isprime(nops(nn)) and andmap(isprime, nn) and isprime(convert(nn, `+`)) then n else fi end: L:=[seq(a(10, k), k=1..10^5)]; U:=[]: for z to 1 do A:=L; for x in L do l:=sort(convert(x, base, 10)); m:=[selectremove(proc(z) sort(convert(z, base, 10))=l end, A)]; if not m[1]=[] then U:=[op(U), min(op(m[1]))]; fi; if m[2]=[] then break else A:=m[2]; fi od od; U;
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Walter Kehowski, Apr 06 2006
STATUS
approved