A158846 -id:A158846 - cp's OEIS frontend

A158853 a(n), a(n+1), a(n+2), for n=5,8,11,... are respectively the numbers of representations of the integers 2^k-2, 2^k, 2^k+2, where k=(n+4)/3, by unordered sums of two odd primes not belonging to A158846.

2, 0, 3, 1, 0, 1, 5, 0, 3, 6, 0, 7, 18, 0, 8, 10, 0, 21, 50, 0, 26, 43, 0, 67, 204, 0, 79, 93, 0, 213, 398, 0, 279, 445, 0, 684, 1649, 0, 630, 1008, 0, 2135, 4890, 0, 3063, 3681, 0, 6852

Offset: 11

Vladimir Shevelev, Mar 28 2009

A158846 A156537

A158847 Removed primes according to algorithm of A156284 beginning with m=6.

Original entry on oeis.org

41, 47, 53, 59, 61, 97, 109, 149, 167, 173, 227, 233, 239, 251, 271, 283, 313, 331, 349, 373, 409, 433, 439, 499, 509, 521, 557, 563, 593, 641, 677, 743, 761, 827, 887, 911, 941, 953, 1013, 1019, 1021, 1039, 1051, 1129, 1171, 1237, 1279, 1291, 1297

Offset: 1

Vladimir Shevelev, Mar 28 2009

Powers 2^m, m>=6, are not expressible as sums of two primes which are not in the sequence

A156284 A158756 A158759 A158846

A158848 Prime numbers p where 2^k-p is prime, with k>6 and minimal.

Original entry on oeis.org

67, 97, 109, 149, 167, 173, 197, 227, 233, 239, 251, 271, 283, 313, 331, 349, 373, 409, 433, 439, 499, 509, 521, 557, 563, 593, 641, 677, 743, 761, 773, 797, 827, 857, 887, 911, 941, 953, 971, 977, 983, 1013, 1019, 1021, 1039, 1051, 1129, 1171, 1237, 1279, 1291, 1297, 1321

Offset: 1

Vladimir Shevelev, Mar 28 2009

nonn

These are the primes removed according to algorithm of A156284 beginning with m=7.

Powers 2^m, m>=7, are not expressible as sums of two primes which are not in the sequence.

Bill McEachen, Table of n, a(n) for n = 1..10000

Cf. A152451, A156284, A158756, A158759, A158846, A158847, A086081.

isok(p) = if (isprime(p), my(k=ceil(log(p)/log(2))); (k >= 7) && isprime(2^k-p)); \\ Michel Marcus, Jan 22 2023

a(n) = A086081(n+11). - Bill McEachen, Jan 22 2023

Missing terms 773, 797, 827, 857 added by Michel Marcus, Jan 23 2023

New name from Bill McEachen, Jan 22 2023

cp's OEIS Frontend

A158853 a(n), a(n+1), a(n+2), for n=5,8,11,... are respectively the numbers of representations of the integers 2^k-2, 2^k, 2^k+2, where k=(n+4)/3, by unordered sums of two odd primes not belonging to A158846.

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A158847 Removed primes according to algorithm of A156284 beginning with m=6.

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A158848 Prime numbers p where 2^k-p is prime, with k>6 and minimal.

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