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A167414 Primes p such that sum of their squared decimal digits, minus one, is prime. 2
2, 127, 149, 211, 251, 271, 277, 347, 419, 457, 491, 521, 523, 541, 547, 587, 727, 743, 853, 857, 941, 1021, 1049, 1061, 1087, 1201, 1223, 1229, 1249, 1289, 1373, 1409, 1423, 1429, 1483, 1553, 1559, 1601, 1621, 1627, 1733, 1753, 1861, 1867, 1951, 1973 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

127 is a term because 1^2 + 2^2 + 7^2 - 1 = 53 (prime);

149 is a term because 1^2 + 4^2 + 9^2 - 1 = 97;

347 is a term because 3^2 + 4^2 + 7^2 - 1 = 73.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1300

MAPLE

A003132 := proc(n) local d; add(d^2, d=convert(n, base, 10)) ; end proc: A167414 := proc(n) local p; if n = 1 then 2; else p := nextprime(procname(n-1)) ; while not isprime(A003132(p)-1) do p := nextprime(p) ; end do ; return p end if ; end proc: seq(A167414(n), n=1..80) ; # R. J. Mathar, Nov 04 2009

MATHEMATICA

Select[Prime[Range[3000]], PrimeQ[Total[IntegerDigits[#]^2] - 1] &] (* Vincenzo Librandi, Sep 25 2014 *)

CROSSREFS

Cf. A167412.

Sequence in context: A064070 A266993 A139904 * A065381 A274123 A141928

Adjacent sequences:  A167411 A167412 A167413 * A167415 A167416 A167417

KEYWORD

nonn,base,changed

AUTHOR

Vincenzo Librandi, Nov 03 2009

EXTENSIONS

2 and terms larger than 941 added by R. J. Mathar, Nov 04 2009

STATUS

approved

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Last modified May 25 04:50 EDT 2019. Contains 323539 sequences. (Running on oeis4.)