A186281 - OEIS

A186281

Primes within A186278.

37, 43, 73, 79, 109, 127, 139, 181, 229, 241, 271, 277, 313, 331, 349, 367, 397, 421, 433, 457, 487, 547, 571, 577, 607, 613, 673, 691, 727, 733, 751, 757, 769, 823, 829, 853, 907, 919, 991, 1009, 1063, 1087, 1093, 1117, 1123, 1171, 1231, 1249, 1279

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

367 is in the sequence because (1) it is prime and (2) the sum of its digits (3 + 6 + 7 = 16) plus the sum of the digits of 367^2 (134689 -> 1 + 3 + 4 + 6 + 8 + 9 = 31) equals 16 + 31 = 47, which is prime.

MATHEMATICA

Select[Prime[Range[300]], PrimeQ[Total[IntegerDigits[#]]+Total[IntegerDigits[#^2]]]&]

CROSSREFS

Cf. A186278, A186279, A186280.

Sequence in context: A109557 A176927 A039950 * A225423 A367478 A322098

Adjacent sequences: A186278 A186279 A186280 * A186282 A186283 A186284

KEYWORD

nonn,easy,base

AUTHOR

Harvey P. Dale, Feb 16 2011

STATUS

approved