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A165493
Primes p where the digital sum of p^2 is equal to 19.
7
17, 37, 53, 73, 89, 107, 109, 127, 181, 199, 269, 271, 379, 503, 521, 557, 701, 739, 1009, 1061, 1097, 1151, 1171, 1439, 1511, 1601, 1619, 1747, 1801, 1871, 2251, 3169, 3259, 3329, 3347, 3511, 3761, 3851, 3889, 4051, 4139, 4519, 4751, 4951, 5003, 5021, 5849
OFFSET
1,1
LINKS
FORMULA
{A000040(i) : A123157(i) = 19} [R. J. Mathar, Sep 29 2009]
EXAMPLE
17 is in the sequence because 17^2=289 and 2+8+9=19.
1801 is in the sequence because 1801^2=3243601 and 3+2+4+3+6+0+1=19.
MAPLE
A007953 := proc(n) add(d, d=convert(n, base, 10)) ; end:
A123157 := proc(n) A007953((ithprime(n))^2) ; end:
for n from 1 to 100000 do if A123157(n) = 19 then printf("%d, ", ithprime(n)) ; fi; od: # R. J. Mathar, Sep 29 2009
MATHEMATICA
Select[Prime[Range[800]], Total[IntegerDigits[#^2]]== 19&] (* Vincenzo Librandi, Jun 24 2013 *)
PROG
(Magma) [p: p in PrimesUpTo(6000) | &+Intseq(p^2) eq 19]; // Bruno Berselli, Jun 24 2013
CROSSREFS
Sequence in context: A217195 A177835 A075698 * A339531 A363040 A295338
KEYWORD
nonn,base
AUTHOR
Vincenzo Librandi, Sep 21 2009
EXTENSIONS
More terms from R. J. Mathar, Sep 29 2009
STATUS
approved