cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A173074 Numbers n such that A171715(n)=2*A173073(n).

Original entry on oeis.org

5, 6, 12, 21, 40, 41, 74, 76, 100, 136, 157, 161, 403, 728, 729, 738, 743, 1476
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Feb 09 2010

Keywords

Comments

Numbers n such that A171715(n)=2*A173073(n). Or, numbers n such that A007645(n)-A003627(n)=2*(A141468(n)-A001477(n)) where A007645 U A003627 U A141468 = A000040 U A141468 = A001477.
No further terms between 1476 and 80000. [From R. J. Mathar, May 02 2010]

Examples

			a(1)=5 because 8=2*4.

Crossrefs

Cf. A000040(the primes), A001477(the nonnegative numbers), A003627(the generalized non-cuban primes), A007645(the generalized cuban primes), A141468 (the nonnegative nonprimes), A171715 (the differences between generalized cuban and non-cuban primes), A173073 (the differences between nonnegative nonprimes and nonnegative numbers).

Formula

A171715(a(n))=2*A173073(a(n)).

Extensions

Terms from 100 up to 1476 from R. J. Mathar, May 02 2010

A172235 n-th partial sum of primes of the form 3*k+1/2+-1/2 minus n-th partial sum of primes of the form 3*m-1.

Original entry on oeis.org

1, 3, 5, 7, 15, 23, 25, 39, 53, 67, 75, 89, 103, 111, 131, 157, 177, 197, 211, 225, 245, 265, 285, 311, 313, 321, 353, 379, 405, 449, 493, 543, 587, 625, 675, 701, 727, 765, 791, 823, 855, 875, 901, 921, 959
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Feb 01 2010

Keywords

Examples

			a(1) = (3*1+1/2-1/2)-(3*1-1) = 1;
a(2) = (3+3*2+1/2+1/2)-(2+3*2-1) = 3.

Crossrefs

Cf. A172188, A172113.
Partial sums of A171715.

Formula

a(n) = A172113(n) - A172188(n).

Extensions

Corrected (453 replaced by 493) by R. J. Mathar, May 22 2010
Showing 1-2 of 2 results.

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