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A006378
Prime self (or Colombian) numbers: primes not expressible as the sum of an integer and its digit sum.
(Formerly M2427)
19
3, 5, 7, 31, 53, 97, 211, 233, 277, 367, 389, 457, 479, 547, 569, 613, 659, 727, 839, 883, 929, 1021, 1087, 1109, 1223, 1289, 1447, 1559, 1627, 1693, 1783, 1873, 2099, 2213, 2347, 2437, 2459, 2503, 2549, 2593, 2617, 2683, 2729, 2819, 2953, 3023, 3067
OFFSET
1,1
REFERENCES
M. Gardner, Time Travel and Other Mathematical Bewilderments. Freeman, NY, 1988, p. 116.
D. R. Kaprekar, Puzzles of the Self-Numbers. 311 Devlali Camp, Devlali, India, 1959.
D. R. Kaprekar, The Mathematics of the New Self Numbers, Privately Printed, 311 Devlali Camp, Devlali, India, 1963.
D. R. Kaprekar, The Mathematics of the New Self Numbers (Part V). 311 Devlali Camp, Devlali, India, 1967.
Jeffrey Shallit, personal communication c. 1999.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Ernest G. Hibbs, Component Interactions of the Prime Numbers, Ph. D. Thesis, Capitol Technology Univ. (2022), see p. 33.
D. R. Kaprekar, The Mathematics of the New Self Numbers [annotated and scanned]
B. Recamán, Problem E2408, Amer. Math. Monthly, 81 (1974), p. 407.
T. Trotter, Charlene Numbers (Copy as of Jan. 2018 on web.archive.org; original page no longer available.) Originally published Nov. 2010.
FORMULA
A107740(A049084(a(n))) = 0. [Corrected by Reinhard Zumkeller, Sep 27 2014]
MATHEMATICA
With[{nn=3200}, Complement[Prime[Range[PrimePi[nn]]], Table[n+Total[ IntegerDigits[n]], {n, nn}]]] (* Harvey P. Dale, Dec 30 2011 *)
PROG
(Haskell)
a006378 n = a006378_list !! (n-1)
a006378_list = map a000040 $ filter ((== 0) . a107740) [1..]
-- Reinhard Zumkeller, Sep 27 2014
(PARI) select( is_A006378(n)=is_A003052(n)&&isprime(n), primes([1, 3000])) \\ M. F. Hasler, Nov 08 2018
CROSSREFS
KEYWORD
nonn,base,nice,easy
STATUS
approved