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A084195 Even numbers n such that the sum of the digits is prime, n/2 is prime and the sum of the digits of n/2 is also prime. 0
14, 58, 94, 122, 166, 274, 278, 302, 346, 382, 386, 454, 458, 526, 562, 566, 634, 674, 706, 746, 818, 922, 926, 1114, 1154, 1198, 1202, 1282, 1286, 1466, 1514, 1594, 1642, 1646, 1774, 1822, 1954, 2038, 2078, 2102, 2182, 2186, 2218, 2258, 2326, 2362 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

5+8=13 for n=58 and 2+9=11 for n/2=29=prime.

1+2+2=5 for n=122 and 6+1=7 for n/2=61=prime.

2+7+8=17 for n=278 and 1+3+9=13 for n/2=139=prime.

PROG

(PARI) isok(n) = {if (n % 2, return (0)); dn = digits(n); dh = digits(n/2); isprime(n/2) && isprime(sum(i=1, #dn, dn[i])) && isprime(sum(i=1, #dh, dh[i])); } \\ Michel Marcus, Aug 12 2013

CROSSREFS

Subsequence of A084194.

Sequence in context: A212675 A041376 A063537 * A033856 A143861 A100174

Adjacent sequences:  A084192 A084193 A084194 * A084196 A084197 A084198

KEYWORD

base,nonn

AUTHOR

Patrick Capelle, Jun 20 2003

EXTENSIONS

More terms from Michel Marcus, Aug 12 2013

STATUS

approved

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Last modified August 22 20:33 EDT 2019. Contains 326185 sequences. (Running on oeis4.)