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A048528
Primes expressible in two ways as the sum of an integer and its digit sum.
2
101, 103, 107, 109, 113, 307, 311, 313, 317, 509, 521, 709, 719, 911, 919, 1009, 1013, 1213, 1217, 1409, 1607, 1609, 1613, 1619, 1621, 1811, 1823, 2017, 2027, 2111, 2113, 2309, 2311, 2521, 2711, 2713, 2719, 2917, 2927, 3011, 3209, 3217, 3221, 3407, 3413, 3613, 3617, 3623
OFFSET
1,1
LINKS
EXAMPLE
313 = 296 + (2+9+6) and 313 = 305 + (3+0+5).
MATHEMATICA
Transpose[Select[Tally[Select[#+Total[IntegerDigits[#]]&/@ Range[ 5000], PrimeQ]], #[[2]]==2&]][[1]] (* Harvey P. Dale, May 09 2013 *)
PROG
(Python)
from collections import Counter
from sympy import isprime
def a_list(upto):
return [i for i, j in Counter([i+sum(map(int, str(i))) for i in range(upto)]).items() if j>1 and isprime(i)]
print(a_list(4000)) # Nicholas Stefan Georgescu, Mar 02 2023
CROSSREFS
Sequence in context: A131687 A327914 A167844 * A164739 A085821 A183087
KEYWORD
nonn,base,nice
AUTHOR
Patrick De Geest, May 15 1999
EXTENSIONS
Corrected and extended by Harvey P. Dale, May 09 2013
STATUS
approved